First-line therapy for people with heart failure due to reduced systolic function should include angiotensin-converting enzyme (ACE) inhibitors (ACE-I) or angiotensin receptor blockers (ARBs) if the person develops a long term cough as a side effect of the ACE-I. Use of medicines from this class is associated with improved survival and quality of life in people with heart failure.

Beta-adrenergic blocking agents (beta blockers) also form part of the first line of treatment, adding to the improvement in symptoms and mortality provided by ACE-I/ARB. The mortality benefits of beta blockers in people with systolic dysfunction who also have atrial fibrillation (AF) is more limited than in those who do not have AF. If the ejection fraction is not diminished (HFpEF), the benefits of beta blockers are more modest; a decrease in mortality has been observed but reduction in hospital admission for uncontrolled symptoms has not been observed.

In people who are intolerant of ACE-I and ARBs or who have significant kidney dysfunction, the use of combined hydralazine and a long-acting nitrate, such as isosorbide dinitrate, is an effective alternate strategy. This regimen has been shown to reduce mortality in people with moderate heart failure. It is especially beneficial in African-Americans (AA). In AAs who are symptomatic, hydralazine and isosorbide dinitrate (H+I) can be added to ACE-I or ARBs.

In people with markedly reduced ejection fraction, the use of an aldosterone antagonist, in addition to beta blockers and ACE-I, can improve symptoms and reduce mortality.

Second-line medications for CHF do not confer a mortality benefit. Digoxin is one such medication. Its narrow therapeutic window, a high degree of toxicity, and the failure of multiple trials to show a mortality benefit have reduced its role in clinical practice. It is now used in only a small number of people with refractory symptoms, who are in atrial fibrillation and/or who have chronic low blood pressure.

Diuretics have been a mainstay of treatment for treatment of fluid accumulation, and include diuretics classes such as loop diuretics, thiazide-like diuretic, and potassium-sparing diuretic. Although widely used, evidence on their efficacy and safety is limited, with the exception of mineralocorticoid antagonists such as spironolactone. Mineralocorticoid antagonists in those under 75 years old appear to decrease the risk of death. A recent Cochrane review found that in small studies, the use of diuretics appeared to have improved mortality in individuals with heart failure. However, the extent to which these results can be extrapolated to a general population is unclear due to the small number of participants in the cited studies.

Anemia is an independent factor in mortality in people with chronic heart failure. The treatment of anemia significantly improves quality of life for those with heart failure, often with a reduction in severity of the NYHA classification, and also improves mortality rates. The latest European guidelines (2012) recommend screening for iron-deficient anemia and treating with parenteral iron if anemia is found.

The decision to anticoagulate people with HF, typically with left ventricular ejection fractions <35% is debated, but generally, people with coexisting atrial fibrillation, a prior embolic event, or conditions which increase the risk of an embolic event such as amyloidosis, left ventricular noncompaction, familial dilated cardiomyopathy, or a thromboembolic event in a first-degree relative.

A person's risk of developing heart failure is inversely related to their level of physical activity. Those who achieved at least 500 MET-minutes/week (the recommended minimum by U.S. guidelines) had lower heart failure risk than individuals who did not report exercising during their free time; the reduction in heart failure risk was even greater in those who engaged in higher levels of physical activity than the recommended minimum.

Marine-derived omega-3 polyunsaturated fatty acids (PUFAs) has been promoted for the prevention of sudden cardiac death due to its postulated ability to lower triglyceride levels, prevent arrhythmias, decrease platelet aggregation, and lower blood pressure. However, according to a recent systematic review, omega-3 PUFA supplementation are not being associated with a lower risk of sudden cardiac death.

An implantable cardioverter defibrillator (ICD) is a battery powered device that monitors electrical activity in the heart and when an arrhythmia or asystole is detected is able to deliver an electrical shock to terminate the abnormal rhythm. ICDs are used to prevent sudden cardiac death (SCD) in those that have survived a prior episode of sudden cardiac arrest (SCA) due to ventricular fibrillation or ventricular tachycardia (secondary prevention). ICDs are also used prophylactically to prevent sudden cardiac death in certain high risk patient populations (primary prevention).

Numerous studies have been conducted on the use of ICDs for the secondary prevention of SCD. These studies have shown improved survival with ICDs compared to the use of anti-arrhythmic drugs. ICD therapy is associated with a 50% relative risk reduction in death caused by an arrhythmia and a 25% relative risk reduction in all cause mortality.

Primary prevention of SCD with ICD therapy for high risk patient populations has similarly shown improved survival rates in a number of large studies. The high risk patient populations in these studies were defined as those with severe ischemic cardiomyopathy (determined by a reduced left ventricular ejection fraction (LVEF)). The LVEF criteria used in these trials ranged from less than or equal to 30% in MADIT-II to less than or equal to 40% in MUSTT.

Despite increasing incidence of HFpEF effective inroads to therapeutics have been largely unsuccessful. Currently, recommendations for treatment are directed at symptom relief and co-morbid conditions. Frequently this involves administration of diuretics to relieve complications associated with volume overload, such as leg swelling and high blood pressure.

Commonly encountered conditions that must be treated for and have independent recommendations for standard of care include atrial fibrillation, coronary artery disease, hypertension, and hyperlipidemia. There are particular factors unique to HFpEF that must be accounted for with therapy. Unfortunately, currently available randomized clinical trials addressing the therapeutic adventure for these conditions in HFpEF present conflicting or limited evidence.

Specific aspects of therapeutics should be avoided in HFpEF to prevent the deterioration of the condition. Considerations that are generalizable to heart failure include avoidance of a fast heart rate, elevations in blood pressure, development of ischemia, and atrial fibrillation. More specific to HFpEF include avoidance of preload reduction. As patients display normal ejection fraction but reduced cardiac output they are especially sensitive to changes in preloading and may rapidly display signs of output failure. This means administration of diuretics and vasodilators must be monitored carefully.

HFrEF and HFpEF represent distinct entities in terms of development and effective therapeutic management. Specifically cardiac resynchronization, administration of beta blockers and angiotensin converting enzyme inhibitors are applied to good effect in HFrEF but are largely ineffective at reducing morbidity and mortality in HFpEF. Many of these therapies are effective in reducing the extent of cardiac dilation and increasing ejection fraction in HFrEF patients. It is unsurprising they fail to effect improvement in HFpEF patients, given their un-dilated phenotype and relative normal ejection fraction. Understanding and targeting mechanisms unique to HFpEF are thus essential to the development of therapeutics.

Randomized studies on HFpEF patients have shown that exercise improves left ventricular diastolic function, the heart's ability to relax, and is associated with improved aerobic exercise capacity. The benefit patients seem to derive from exercise does not seem to be a direct cardiac effect but rather is due to changes in peripheral vasculature and skeletal muscle, which show abnormalities in HFpEF patients.

Patients should be regularly assessed to determine progression of the condition, response to interventions, and need for alteration of therapy. Ability to perform daily tasks, hemodynamic status, kidney function, electrolyte balance, and serum natriuretic peptide levels are important parameters. Behavioral management is important in these patients and it is recommended that individuals with HFpEF avoid alcohol, smoking, and high sodium intake.

Some appetite suppressant drugs such as fenfluramine (which in combination with phentermine was marketed as "Pondimin" and commonly referred to as fen-phen), chlorphentermine, and aminorex (along with its analogue 4-Methylaminorex which has seen sporadic use as a recreational drug) induce a similar pattern of cardiac fibrosis (and pulmonary hypertension), apparently by over-stimulating 5HT receptors on the cardiac fibroblast cells.

These drugs consequently tend to cause increased risk of heart valve damage and subsequent heart failure, which eventually led to them being withdrawn from the market.

Many factors influence the time course and extent of remodeling, including the severity of the injury, secondary events (recurrent ischemia or infarction), neurohormonal activation, genetic factors and gene expression, and treatment. Medications may attenuate remodeling. Angiotensin-converting enzyme (ACE) inhibitors have been consistently shown to decrease remodeling in animal models or transmural infarction and chronic pressure overload. Clinical trials have shown that ACE inhibitor therapy after myocardial infarction leads to improved myocardial performance, improved ejection fraction, and decreased mortality compared to patients treated with placebo. Likewise, inhibition of aldosterone, either directly or indirectly, leads to improvement in remodeling. Carvedilol, a 3rd generation beta blocker, may actually reverse the remodeling process by reducing left ventricular volumes and improving systolic function. Early correction of congenital heart defects, if appropriate, may prevent remodeling, as will treatment of chronic hypertension or valvular heart disease. Often, reverse remodeling, or improvement in left ventricular function, will also be seen.

As previously stated, management of HFpEF is primarily dependent on the treatment of symptoms and exacerbating conditions. Currently treatment with ACE inhibitors, calcium channel blockers, beta blockers, and angiotensin receptor blockers are employed but do not have a proven benefit in HFpEF patients. Additionally, use of Diuretics or other therapies that can alter loading conditions or blood pressure should be used with caution. It is not recommended that patients be treated with phosphodiesterase-5-inhibitors or digoxin.

Antimineralocorticoid is currently recommended for patients with HFpEF who show elevated brain natriuretic peptide levels. Spironolactone is the first member of this drug class and the most frequently employed. Care should be taken to monitor serum potassium levels as well as kidney function, specifically glomerular filtration rate during treatment.

Beta blockers play a rather obscure role in HFpEF treatment but appear to play a beneficial role in patient management. There is currently a deficit of clinical evidence to support a particular benefit for HFpEF patients, with most evidence resulting from HFpEF patients' inclusion in broader heart failure trials. However, some evidence suggests that vasodilating beta blockers, such as nebivolol, can provide a benefit for patients with heart failure regardless of ejection fraction. Additionally, because of the chronotropic perturbation and diminished LV filling seen in HFpEF the bradycardic effect of beta blockers may enable improved filling, reduced myocardial oxygen demand and lowered blood pressure. However, this effect also can contribute to diminished response to exercise demands and can result in an excessive reduction in heart rate.

ACE inhibitors do not appear to improve morbidity or mortality associated with HFpEF alone. However, they are important in the management of hypertension, a significant player in the pathophysiology of HFpEF.

Angiotensin II receptor blocker treatment shows an improvement in diastolic dysfunction and hypertension that is comparable to other anti-hypertensive medication.

Elevated prevalence of cardiac fibrosis and related valvopathies was found to be associated with use of a number of unrelated drugs following long-term statistical analysis once the drugs had been on the market for some time. The cause of this was unknown at the time, but eventually it was realised that all the implicated drugs acted as agonists at 5-HT receptors in the heart in addition to their intended sites of action elsewhere in the body.

The precise mechanisms involved remain elusive however, as while the cardiotoxicity shows some dose-response relationship, it does not always develop, and consistent daily use over an extended period tends to be most strongly predictive of development of valvopathy.

The drugs most classically associated with the condition are weight loss drugs such as fenfluramine and chlorphentermine, and antiparkinson drugs such as pergolide and cabergoline, which are prescribed to be taken several times a day, often for months or years at a time.

Drugs which act as 5-HT agonists tend to be less likely to cause heart problems when used sparingly.

The heart valve changes seen with moderate and intermittent use can result in permanent damage and life-threatening heart problems if use of the causative drug is increased or continued, however longitudinal studies of former patients suggest that the damage will heal over time to some extent at least.

Current treatment options for Boxer cardiomyopathy are largely restricted to the use of oral anti-arrhythmic medications. The aim of therapy is to minimize ventricular ectopy, eliminate syncopal episodes, and prevent sudden cardiac death. A number of medications have been used for this purpose, including atenolol, procainamide, sotalol, mexiletine, and amiodarone. Combinations can also be used. Sotalol is probably the most commonly used antiarrhythmic at this time. It has been demonstrated that sotalol alone, or a combination of mexiletine and atenolol, results in a reduction in the frequency and complexity of ventricular ectopy. It is likely that these medications also reduce syncopal episodes, and it is hoped this extends to a reduced risk of sudden death. Consequently, antiarrhythmic therapy is typically recommended by veterinary cardiologists for Boxer dogs with ARVC. Although relatively rare, oral antiarrhythmic medications may be proarrhythmic in some dogs; consequently, appropriate monitoring and follow-up is recommended.

The ideal therapy for Boxer cardiomyopathy would be implantation of an implantable cardioverter-defibrillator (ICD). This has been attempted in a limited number of dogs. Unfortunately, ICDs are programmed for humans and the algorithms used are not appropriate for dogs, increasing the risk of inappropriate shocks. In the future, reprogramming of ICDs may allow them to emerge as a viable option in the treatment for Boxer cardiomyopathy.

The prognosis for TIC after treatment of the underlying tachyarrhythmia is generally good. Studies show that left ventricular function often improves within 1 month of treatment of the tachyarrhythmia, and normalization of the left ventricular ejection fraction occurs in the majority of patients by 3 to 4 months. In some patients however, recovery of this function can take greater than 1 year or be incomplete. In addition, despite improvement in the left ventricular ejection fraction, studies have demonstrated that patients with prior TIC continue to demonstrate signs of negative cardiac remodeling including increased left ventricular end-systolic dimension, end-systolic volume, and end-diastolic volume. Additionally, recurrence of the tachyarrhythmia in patients with a history of TIC has been associated with a rapid decline in left ventricular ejection fraction and more severe cardiomyopathy that their prior presentation, which may be a result of the negative cardiac remodeling. There have also been cases of sudden death in patients with a history of TIC, which may be associated with worse baseline left ventricular dysfunction. Given these risks, routine monitoring with clinic visits, ECG, and echocardiography is recommended.

Isolated PVCs with benign characteristics require no treatment.

In healthy individuals, PVCs can often be resolved by restoring the balance of magnesium, calcium and potassium within the body. In one randomized controlled trial with 60 people those with 260 mg magnesium daily supplementation (in magnesium pidolate) had an average reduction of PVC by 77%. In another trial with 232 persons with frequent ventricular arrhythmias (> 720 PVC/24 h) those with 6 mmol of magnesium (146 mg Mg)/12 mmol of potassium-DL-hydrogenaspartate daily supplementation had median reduction of PVCs by 17%.

The most effective treatment is the elimination of triggers (particularly stopping the use of substances such as caffeine and certain drugs, like tobacco).

- Medications

- Antiarrhythmics: these agents alter the electrophysiologic mechanisms responsible for PVCs. In CAST study of survivors of myocardial infarction encainide and flecainide, although could suppress PVC, they increased death risk; moricizine increased death rate when used with diuretics and decreased it when used alone.

- Beta blockers

- Calcium channel blockers

- Electrolytes replacement

- Magnesium supplements (e.g. magnesium citrate, orotate, Maalox, etc.)

- Potassium supplements (e.g. chloride potassium with citrate ion)

- Radiofrequency catheter ablation treatment. It is advised for people with ventricular dysfunction and frequent arrhythmias or very frequent PVC (>20% in 24 h) and normal ventricular function. This procedure is a way to destroy the area of the heart tissue that is causing the irregular contractions characteristic of PVCs using radio frequency energy.

- Implantable cardioverter-defibrillator

- Lifestyle modification

- Frequently stressed individuals should consider therapy, or joining a support group.

- Heart attacks can increase the likelihood of having PVCs.

In the setting of existing heart disease, however, PVCs must be watched carefully, as they may cause a form of ventricular tachycardia (rapid heartbeat).

The American College of Cardiology and the American Heart Association recommend evaluation for coronary artery disease (CAD) in patients who have frequent PVCs and cardiac risk factors, such as hypertension and smoking (SOR C). Evaluation for CAD may include stress testing, echocardiography, and ambulatory rhythm monitoring.

Treatment of TIC involves treating both the tachyarrhythmia and the heart failure with the goal of adequate rate control or restoration of the normal heart rhythm (aka. normal sinus rhythm) to reverse the cardiomyopathy. The treatment of the tachyarrhythmia depends on the specific arrhythmia, but possible treatment modalities include rate control, rhythm control with antiarrhythmic agents and cardioversion, radiofrequency (RF) catheter ablation, or AV node ablation with permanent pacemaker implantation.

For TIC due to atrial fibrillation, rate control, rhythm control, and RF catheter ablation can be effective to control the tachyarrhythmia and improve left ventricular systolic function. For TIC due to atrial flutter, rate control is often difficult to achieve, and RF catheter ablation has a relatively high success rate with a low risk of complications. In patients with TIC due to other types of SVT, RF catheter ablation is recommended as a first-line treatment. In patients with TIC due to VT or PVCs, both antiarrhythmics and RF catheter ablation can be used. However, the options for antiarrhythmic agents are limited because certain agents can be proarrhythmic in the setting of myocardial dysfunction in TIC. Therefore, RF catheter ablation is often a safe and effective choice for treatment VT and PVCs causing TIC. In cases where other treatment strategies fail, AV node ablation with permanent pacemaker implantation can also be used to treat the tachyarrhythmia.

The treatment of heart failure commonly involves neurohormonal blockade with beta-blockers and angiotensin convertase inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) along with symptomatic management with diuretics. Beta-blockers and ACE inhibitors can inhibit and potentially reverse the negative cardiac remodeling, which refers to structural changes in the heart, that occurs in TIC. However, the need to continue these agents after treatment of the tacharrhythmia and resolution of left ventricular systolic dysfunction remains controversial.

At present, there is no effective specific treatment available for diabetic cardiomyopathy. Treatment centers around intense glycemic control through diet, oral hypoglycemics and frequently insulin and management of heart failure symptoms. There is a clear correlation between increased glycemia and risk of developing diabetic cardiomyopathy, therefore, keeping glucose concentrations as controlled as possible is paramount. Thiazolidinediones are not recommended in patients with NYHA Class III or IV heart failure secondary to fluid retention.

As with most other heart diseases, ACE inhibitors can also be administered. An analysis of major clinical trials shows that diabetic patients with heart failure benefit from such a therapy to a similar degree as non-diabetics. Similarly, beta blockers are also common in the treatment of heart failure concurrently with ACE inhibitors.

The prognosis of tricuspid insufficiency is less favorable for males than females. Furthermore, increased tricuspid insufficiency (regurgitation) severity is an indication of a poorer prognosis according to Nath, et al. It is also important to note that since tricuspid insufficiency most often arises from left heart failure or pulmonary hypertension, the person's prognosis is usually dictated by the prognosis of the latter conditions and not by the tricuspid insufficiency "per se".

As an overall medical condition PVCs are normally not very harmful to patients that experience them, but frequent PVCs may put patients at increased risk of developing arrhythmias or cardiomyopathy, which can greatly impact the functioning of the heart over the span of that patient's life. On a more serious and severe scale, frequent PVCs can accompany underlying heart disease and lead to chaotic, dangerous heart rhythms and possibly sudden cardiac death.

Asymptomatic patients that do not have heart disease have long-term prognoses very similar to the general population, but asymptomatic patients that have ejection fractions greater than 40% have a 3.5% incidence of sustained ventricular tachycardia or cardiac arrest. One drawback comes from emerging data that suggests very frequent ventricular ectopy may be associated with cardiomyopathy through a mechanism thought to be similar to that of chronic right ventricular pacing associated cardiomyopathy. Patients that have underlying chronic structural heart disease and complex ectopy, mortality is significantly increased.

In meta-analysis of 11 studies, people with frequent PVC (≥1 time during a standard electrocardiographic recording or ≥30 times over a 1-hour recording) had risk of cardiac death 2 times higher than persons without frequent PVC. Although most studies made attempts to exclude high-risk subjects, such as those with histories of cardiovascular disease, they did not test participants for underlying structural heart disease.

In a study of 239 people with frequent PVCs (>1000 beats/day) and without structural heart disease (i.e. in the presence of normal heart function) there were no serious cardiac events through 5.6 years on average, but there was correlation between PVC prevalence and decrease of ejection fraction and increase of left ventricular diastolic dimension. In this study absence of heart of disease was excluded by echocardiography, cardiac magnetic resonance imaging in 63 persons and Holter monitoring.

Another study has suggested that in the absence of structural heart disease even frequent (> 60/h or 1/min) and complex PVCs are associated with a benign prognosis. It was study of 70 people followed by 6.5 years on average. Healthy status was confirmed by extensive noninvasive cardiologic examination, although cardiac catheterization of a subgroup disclosed serious coronary artery disease in 19%. Overall survival was better than expected.

On the other hand, the Framingham Heart Study reported that PVCs in apparently healthy people were associated with a twofold increase in the risk of all-cause mortality, myocardial infarction and cardiac death. In men with coronary heart disease and in women with or without coronary heart disease, complex or frequent arrhythmias were not associated with an increased risk. The at-risk people might have subclinical coronary disease. These Framingham results have been criticised for the lack of rigorous measures to exclude the potential confounder of underlying heart disease.

In the ARIC study of 14,783 people followed for 15 to 17 years those with detected PVC during 2 minute ECG, and without hypertension or diabetes on the beginning, had risk of stroke increased by 109%. Hypertension or diabetes, both risk factors for stroke, did not change significantly risk of stroke for people with PVC. It is possible that PVCs identified those at risk of stroke with blood pressure and impaired glucose tolerance on a continuum of risk below conventional diagnostic thresholds for hypertension and diabetes. Those in ARIC study with any PVC had risk of heart failure increased by 63% and were >2 times as likely to die due to coronary heart disease (CHD). Risk was also higher for people with or without baseline CHD.

In the Niigata study of 63,386 people with 10-year follow-up period those with PVC during a 10-second recording had risk of atrial fibrillation increased nearly 3 times independently from risk factors: age, male sex, body mass index, hypertension, systolic and diastolic blood pressure, and diabetes.

Reducing frequent PVC (>20%) by antiarrhythmic drugs or by catheter ablation significantly improves heart performance.

Recent studies have shown that those subjects who have an extremely high occurrence of PVCs (several thousand a day) can develop dilated cardiomyopathy. In these cases, if the PVCs are reduced or removed (for example, via ablation therapy) the cardiomyopathy usually regresses.

Also, PVCs can permanently cease without any treatment, in a material percentage of cases.

Boxer cardiomyopathy is a genetic disease inherited in an autosomal dominant pattern. The presentation in affected offspring is quite variable, suggesting incomplete penetrance. In 2009, a group led by Dr. Kathryn Meurs at Washington State University announced that they had identified one genetic anomaly associated with Boxer cardiomyopathy but as of 2012 there is still debate over the significance of the discovery.

Arrhythmias due to medications have been reported since the 1920s with the use of quinine. In the 1960s and 1970s problems with antihistamines and antipsychotics were discovered. It was not until the 1980s that the underlying issue, QTc prolongation was determined.

If untreated, this abnormal heart rhythm can lead to dizziness, chest pain, a sensation of fluttering or pounding in the chest (palpitations), shortness of breath, or fainting (syncope). Atrial fibrillation also increases the risk of stroke. Complications of familial atrial fibrillation can occur at any age, although some people with this heart condition never experience any health problems associated with the disorder.

Atrial fibrillation is the most common type of sustained abnormal heart rhythm (arrhythmia), affecting more than 3 million people in the United States. The risk of developing this irregular heart rhythm increases with age. The incidence of the familial form of atrial fibrillation is unknown; however, recent studies suggest that up to 30 percent of all people with atrial fibrillation may have a history of the condition in their family.

In cardiology, ventricular remodeling (or cardiac remodeling) refers to changes in the size, shape, structure, and function of the heart. This can happen as a result of exercise (physiological remodeling) or after injury to the heart muscle (pathological remodeling). The injury is typically due to acute myocardial infarction (usually transmural or ST segment elevation infarction), but may be from a number of causes that result in increased pressure or volume, causing pressure overload or volume overload (forms of strain) on the heart. Chronic hypertension, congenital heart disease with intracardiac shunting, and valvular heart disease may also lead to remodeling. After the insult occurs, a series of histopathological and structural changes occur in the left ventricular myocardium that lead to progressive decline in left ventricular performance. Ultimately, ventricular remodeling may result in diminished contractile (systolic) function and reduced stroke volume.

Physiological remodeling is reversible while pathological remodeling is mostly irreversible. Remodeling of the ventricles under left/right pressure demand make mismatches inevitable. Pathologic pressure mismatches between the pulmonary and systemic circulation guide compensatory remodeling of the left and right ventricles. The term "reverse remodeling" in cardiology implies an improvement in ventricular mechanics and function following a remote injury or pathological process.

Ventricular remodeling may include ventricular hypertrophy, ventricular dilation, cardiomegaly, and other changes. It is an aspect of cardiomyopathy, of which there are many types. Concentric hypertrophy is due to pressure overload, while eccentric hypertrophy is due to volume overload.

In terms of treatment for tricuspid insufficiency prosthetic valve substitutes can be used, though artificial prostheses may cause thrombo‐embolic phenomena(bioprostheses may have a degeneration problem). Some evidence suggests that there are no significant differences between a mechanical or biological tricuspid valve in a recipient.

Generally, surgical treatment of tricuspid regurgitation is not indicated when it has arisen as a result of right ventricular dilatation. In such instances of secondary tricuspid regurgitation, the mainstay of therapy is medical. When left-sided heart failure is the cause, the individual is instructed to decrease intake of salt. Medications in this case may include diuretics and angiotensin-converting enzyme inhibitors.

Premature atrial contractions are often benign, requiring no treatment. Occasionally, the patient having the PAC will find these symptoms bothersome, in which case the doctor may treat the PACs. Sometimes the PACs can indicate heart disease or an increased risk for other cardiac arrhythmias. In this case the underlying cause is treated. Often a beta blocker will be prescribed for symptomatic PACs.

The cause of sudden death in Brugada syndrome is ventricular fibrillation (VF). The average age of death is 41. According to clinical reports, sudden death in people with Brugada syndrome most often happens during sleep. The episodes of syncope (fainting) and sudden death (aborted or not) are caused by fast polymorphic ventricular tachycardias or ventricular fibrillation. These arrhythmias appear with no warning. While there is no exact treatment modality that reliably and totally prevents ventricular fibrillation from occurring in this syndrome, treatment lies in termination of this lethal arrhythmia before it causes death. This is done via insertion of an implantable cardioverter-defibrillator (ICD), which continuously monitors the heart rhythm and will shock the wearer if ventricular fibrillation is sensed.

Studies have evaluated the role of quinidine, a Class Ia antiarrhythmic drug, for decreasing VF episodes occurring in this syndrome. Quinidine has been found to both decrease the number of VF episodes and correct spontaneous ECG changes, possibly via inhibiting I channels.

Some drugs have been reported to induce the type-1 ECG and/or (fatal) arrhythmias in Brugada syndrome patients. Patients with Brugada syndrome can prevent arrhythmias by avoiding these drugs or using them only in controlled conditions. Those with risk factors for coronary artery disease may require an angiogram before ICD implantation.

Most cases are fatal. Automated external defibrillators have helped increase the survival rate to 35%. Defibrillation must be started as soon as possible (within 3 minutes) for maximal benefit. Commotio cordis is the leading cause of fatalities in youth baseball in the US, with two to three deaths per year. It has been recommended that "communities and school districts reexamine the need for accessible automatic defibrillators and cardiopulmonary resuscitation-trained coaches at organized sporting events for children."

Medical management of patients with CRS is often challenging as focus on treatment of one organ may have worsening outcome on the other. It is known that many of the medications used to treat HF may worsen kidney function. In addition, many trials on HF excluded patients with advanced kidney dysfunction. Therefore, our understanding of CRS management is still limited to this date.

Diuretics

ACEI, ARB, renin inhibitors, aldosterone inhibitors

Natriuretic peptides

Vasopressin antagonists

Adenosine antagonists

Ultrafiltration

Inotropes