In people with symptoms, digoxin and diuretics may help. For people with moderate to severe dysfunction, cardiac function can be supported by use of inotropes such as milrinone in the acute phase, followed by oral therapy with ACE inhibitors when tolerated.

In several small case series and randomized control trials, systemic corticosteroids have shown to have beneficial effects in people with proven myocarditis. However, data on the usefulness of corticosteroids should be interpreted with caution, since 58% of adults recover spontaneously, while most studies on children lack control groups.

A 2015 Cochrane review found no evidence of benefit of using intravenous immunoglobulin (IVIG) in adults and tentative benefit in certain children. It is not recommended routinely until there is better evidence.

As with most viral infections, symptomatic treatment is the only form of therapy for most forms of myocarditis.

In the acute phase, supportive therapy, including bed rest, is indicated.

Following a heart attack, nitrates, when taken for two days, and ACE-inhibitors decrease the risk of death. Other medications include:

Aspirin is continued indefinitely, as well as another antiplatelet agent such as clopidogrel or ticagrelor ("dual antiplatelet therapy" or DAPT) for up to twelve months. If someone has another medical condition that requires anticoagulation (e.g. with warfarin) this may need to be adjusted based on risk of further cardiac events as well as bleeding risk. In those who have had a stent, more than 12 months of clopidogrel plus aspirin does not affect the risk of death.

Beta blocker therapy such as metoprolol or carvedilol is recommended to be started within 24 hours, provided there is no acute heart failure or heart block. The dose should be increased to the highest tolerated. Contrary to what was long believed, the use of beta blockers does not appear to affect the risk of death, possibly because other treatments for MI have improved. When beta blocker medication is given within the first 24–72 hours of a STEMI no lives are saved. However, 1 in 200 people were prevented from a repeat heart attack, and another 1 in 200 from having an abnormal heart rhythm. Additionally, for 1 in 91 the medication causes a temporary decrease in the heart's ability to pump blood.

ACE inhibitor therapy should be started within 24 hours, and continued indefinitely at the highest tolerated dose. This is provided there is no evidence of worsening kidney failure, high potassium, low blood pressure, or known narrowing of the renal arteries. Those who cannot tolerate ACE inhibitors may be treated with an angiotensin II receptor antagonist.

Statin therapy has been shown to reduce mortality and subsequent cardiac events, and should be commenced with the aim of lowering LDL cholesterol. Other medications, such as ezetimibe, may also be added with this goal in mind.

Aldosterone antagonists (spironolactone or eplerenone) may be used if there is evidence of left ventricular dysfunction after an MI, ideally after beginning treatment with an ACE inhibitor.

The pain associated with myocardial infarction may be treated with nitroglycerin or morphine. Nitroglycerin (given under the tongue or intravenously) may improve the blood supply to the heart, and decrease the work the heart must do. It is an important part of therapy for its pain relief, despite there being no benefit to overall mortality. Morphine may also be used, and is effective for the pain associated with STEMI. The evidence for benefit from morphine on overall outcomes, however, is poor and there is some evidence of potential harm.

Patients with uncomplicated acute pericarditis can generally be treated and followed up in an outpatient clinic. However, those with high risk factors for developing complications (see above) will need to be admitted to an inpatient service, most likely an ICU setting. High risk patients include the following:

- subacute onset

- high fever (> 100.4 F/38 C) and leukocytosis

- development of cardiac tamponade

- large pericardial effusion (echo-free space > 20 mm) resistant to NSAID treatment

- immunocompromised

- history of oral anticoagulation therapy

- acute trauma

- failure to respond to seven days of NSAID treatment

Pericardiocentesis is a procedure whereby the fluid in a pericardial effusion is removed through a needle. It is performed under the following conditions:

- presence of moderate or severe cardiac tamponade

- diagnostic purpose for suspected purulent, tuberculosis, or neoplastic pericarditis

- persistent symptomatic pericardial effusion

NSAIDs in "viral" or "idiopathic" pericarditis. In patients with underlying causes other than viral, the specific etiology should be treated. With idiopathic or viral pericarditis, NSAID is the mainstay treatment. Goal of therapy is to reduce pain and inflammation. The course of the disease may not be affected. The preferred NSAID is ibuprofen because of rare side effects, better effect on coronary flow, and larger dose range. Depending on severity, dosing is between 300–800 mg every 6–8 hours for days or weeks as needed. An alternative protocol is aspirin 800 mg every 6–8 hours. Dose tapering of NSAIDs may be needed. In pericarditis following acute myocardial infarction, NSAIDs other than aspirin should be avoided since they can impair scar formation. As with all NSAID use, GI protection should be engaged. Failure to respond to NSAIDs within one week (indicated by persistence of fever, worsening of condition, new pericardial effusion, or continuing chest pain) likely indicates that a cause other than viral or idiopathic is in process.

Colchicine, which has been essential to treat recurrent pericarditis, has been supported for routine use in acute pericarditis by recent prospective studies. Colchicine can be given 0.6 mg twice a day (0.6 mg daily for patients <70 kg) for 3 months following an acute attack. It should be considered in all patients with acute pericarditis, preferably in combination with a short-course of NSAIDs. For patients with a first episode of acute idiopathic or viral pericarditis, they should be treated with an NSAID plus colchicine 1–2 mg on first day followed by 0.5 daily or twice daily for three months. It should be avoided or used with caution in patients with severe renal insufficiency, hepatobiliary dysfunction, blood dyscrasias, and gastrointestinal motility disorders.

Corticosteroids are usually used in those cases that are clearly refractory to NSAIDs and colchicine and a specific cause has not been found. Systemic corticosteroids are usually reserved for those with autoimmune disease.

The treatment in viral or idiopathic pericarditis is with aspirin, or non-steroidal anti-inflammatory drugs (NSAIDs such as ibuprofen). Colchicine may be added to the above as it decreases the risk of further episodes of pericarditis.

Severe cases may require one or more of the following:

- pericardiocentesis to treat pericardial effusion/tamponade

- antibiotics to treat tuberculosis or other bacterial causes.

- steroids are used in acute pericarditis but are not favored because they increase the chance of recurrent pericarditis.

- in rare cases, surgery

- in cases of constrictive pericarditis, pericardiectomy

One of the most feared complications of acute pericarditis is cardiac tamponade. Cardiac tamponade is accumulation of enough fluid in the pericardial space --- pericardial effusion --- to cause serious obstruction to the inflow of blood to the heart. Signs of cardiac tamponade include distended neck veins, muffled heart sounds when listening with a stethoscope, and low blood pressure (together known as Beck's triad). This condition can be fatal if not immediately treated.

Another longer term complication of pericarditis, if it recurs over a longer period of time (normally more than 3 months), is progression to constrictive pericarditis. Recent studies have shown this to be an uncommon complication. The definitive treatment for constrictive pericarditis is pericardial stripping, which is a surgical procedure where the entire pericardium is peeled away from the heart.

Due to its rarity, no comprehensive treatment studies on eosinophilic myocarditis have been conducted. Small studies and case reports have directed efforts towards: a) supporting cardiac function by relieving heart failure and suppressing life-threatening abnormal heart rhythms; b) suppressing eosinophil-based cardiac inflammation; and c) treating the underlying disorder. In all cases of symptomatic eosinophilic myocarditis that lack specific treatment regimens for the underlying disorder, available studies recommend treating the inflammatory component of this disorder with non-specific immunosuppressive drugs, principally high-dosage followed by slowly-tapering to a low-dosage maintenance corticosteroid regimens. It is recommended that afflicted individuals who fail this regimen or present with cardiogenic shock be treated with other non-specific immunosuppressive drugs viz., azathioprine or cyclophosphamide, as adjuncts to, or replacements for, corticosteroids. However, individuals with an underlying therapeutically accessible disease should be treated for this disease; in seriously symptomatic cases, such individuals may be treated concurrently with a corticosteroid regimen. Examples of diseases underlying eosinophilic myocarditis that are recommended for treatments directed at the underlying disease include:

- Infectious agents: specific drug treatment of helminth and protozoan infections typically takes precedence over non-specific immunosuppressive therapy, which, if used without specific treatment, could worsen the infection. In moderate-to-severe cases, non-specific immunosuppression is used in combination with specific drug treatment.

- Toxic reactions to ingested agents: discontinuance of the ingested agent plus corticosteroids or other non-specific immunosuppressive regimens.

- Clonal eosinophilia caused by mutations in genes that are highly susceptible to tyrosine kinase inhibitors such as "PDGFRA", "PDGFRB", or possibly "FGFR1": first generation tyrosine kinase inhibitors (e.g. imatinib) are recommended for the former two mutations; a later generation tyrosine kinase inhibitors, ponatinib, alone or combined with bone marrow transplantation, may be useful for treating the FGFR1 mutations.

- Clonal hypereosinophilia due to mutations in other genes or primary malignancies: specific treatment regimens used for these pre-malignant or malignant diseases may be more useful and necessary than non-specific immunosuppression.

- Allergic and autoimmune diseases: non-specific treatment regimens used for these diseases may be useful in place of a simple corticosteroid regimen. For example, eosinophilic granulomatosis with polyangiitis can be successfully treated with mepolizumab.

- Idiopathic hypereosinphilic syndrome and lymphocyte-variant hypereosinophilia: corticosteroids; for individuals with these hypereosinophilias that are refractory to or break through corticosteroid therapy and individuals requiring corticosteroid-sparing therapy, recommended alternative drug therapies include hydroxyurea, Pegylated interferon-α, and either one of two tyrosine kinase inhibitors viz., imatinib and mepolizumab).

Aggressive risk factor modification is required for effective treatment of microvascular angina where exercise plays a major role. Several other treatment strategies including b-blockers, angiotensin-converting enzyme inhibitors, ranolazine, l-arginine, statin drugs and potentially estrogen replacement therapy have been shown to relieve anginal symptoms as well as improve vascular function. Nitrates may be effective for symptom relief. Further studies are required to determine whether specific treatments are associated with improved survival as well as decreased symptoms.

The most specific medicine to treat angina is nitroglycerin. It is a potent vasodilator that decreases myocardial oxygen demand by decreasing the heart's workload. Beta blockers and calcium channel blockers act to decrease the heart's workload, and thus its requirement for oxygen. Nitroglycerin should not be given if certain inhibitors such as sildenafil, tadalafil, or vardenafil have been taken within the previous 12 hours as the combination of the two could cause a serious drop in blood pressure. Treatments for angina are balloon angioplasty, in which the balloon is inserted at the end of a catheter and inflated to widen the arterial lumen. Stents to maintain the arterial widening are often used at the same time. Coronary bypass surgery involves bypassing constricted arteries with venous grafts. This is much more invasive than angioplasty.

The main goals of treatment in angina pectoris are relief of symptoms, slowing progression of the disease, and reduction of future events, especially heart attacks and death. Beta blockers (e.g., carvedilol, propranolol, atenolol) have a large body of evidence in morbidity and mortality benefits (fewer symptoms, less disability and longer life) and short-acting nitroglycerin medications have been used since 1879 for symptomatic relief of angina. Calcium channel blockers (such as nifedipine (Adalat) and amlodipine), isosorbide mononitrate and nicorandil are vasodilators commonly used in chronic stable angina. A new therapeutic class, called If inhibitor, has recently been made available: Ivabradine provides pure heart rate reduction leading to major anti-ischemic and antianginal efficacy. ACE inhibitors are also vasodilators with both symptomatic and prognostic benefit. Statins are the most frequently used lipid/cholesterol modifiers, which probably also stabilize existing atheromatous plaque. Low-dose aspirin decreases the risk of heart attack in patients with chronic stable angina, and was part of standard treatment. However, in patients without established cardiovascular disease, the increase in hemorrhagic stroke and gastrointestinal bleeding offsets any benefits and it is no longer advised unless the risk of myocardial infarction is very high.

Exercise is also a very good long-term treatment for the angina (but only particular regimens - gentle and sustained exercise rather than intense short bursts), probably working by complex mechanisms such as improving blood pressure and promoting coronary artery collateralisation.

Though sometimes used by patients, evidence does not support the use of Traditional Chinese Herbal Products (THCP) for angina

Identifying and treating risk factors for further coronary heart disease is a priority in patients with angina. This means testing for elevated cholesterol and other fats in the blood, diabetes and hypertension (high blood pressure), and encouraging smoking cessation and weight optimization.

The calcium channel blocker nifedipine prolongs cardiovascular event- and procedure-free survival in patients with coronary artery disease. New overt heart failures were reduced by 29% compared to placebo; however, the mortality rate difference between the two groups was statistically insignificant.

Dressler syndrome is best treated with high dose aspirin. In some resistant cases, corticosteroids can be used but are not preferred (avoided) in first month due to the high frequency of impaired ventricular healing leading to increased rate of ventricular rupture. NSAIDs though once used to treat Dressler syndrome, are less advocated and should be avoided in patients with ischemic heart disease. One NSAID in particular, indomethacin, can inhibit new collagen deposition thus impairing the healing process for the infarcted region. NSAIDS should only be used in cases refractory to aspirin. Heparin in Dressler syndrome should be avoided because it can lead to hemorrhage into the pericardial sac leading to tamponade. The only time heparin could be used with pericarditis is with coexisting acute MI in order to prevent further thrombus formation.

Initial therapy of acute decompensated heart failure usually includes some combination of a vasodilator such as nitroglycerin, a loop diuretic such as furosemide, and non-invasive positive pressure ventilation (NIPPV).

Even if symptoms of heart failure are not present, medications can be used to treat the symptoms that are being experienced. These medicines work to control these symptoms as well as treat other health problems that might be present. They can work to improve the quality of life, slow down the progression of heart failure and reduce the risk for other complications that can occur due to heart failure. It is very important to take proper medicines exactly as prescribed by the physician.

A number of different medications are required for people who are experiencing heart failure. Common types of medications that are prescribed for heart failure patients include ACE inhibitors, vasodilators, beta blockers, aspirin, calcium channel blockers, and cholesterol lowering medications such as statins. Depending on the type of damage a patient has suffered and the underlying cause of the heart failure, any of these drug classes or a combination of them can be prescribed. Patients with heart pumping problems will use a different medication combination than those who are experiencing problems with the heart's ability to fill properly during diastole. Potentially dangerous drug interactions can occur when different drugs mix together and work against each other.

Nitrates such as nitroglycerin are often used as part of the initial therapy for ADHF.

Another option is nesiritide, although it should only be considered if conventional therapy has been ineffective or contraindicated as it is much more expensive than nitroglycerine and has not been shown to be of any greater benefit.

Mortality in HIV-infected patients with cardiomyopathy is increased independently of CD4 count, age, sex, and HIV risk group.

The therapy is similar to therapy for non-ischemic cardiomyopathy: after medical therapy is begun, serial echocardiographic studies should be performed at 4-months intervals. If function continues to worsen or the clinical course deteriorates, a biopsy should be considered.

HAART has reduced the incidence of myocarditis thus reducing the prevalence of HIV-associated cardiomyopathy by about 30% in developed countries. However, the prevalence in developing countries is 32% and increasing as HAART is scarce – not to mention the effects of other risk factors such as high cholesterol and lipid diet. IVIGs can also help patients with HIV-associated myocarditis as mentioned earlier.

There are a number of treatment options for coronary artery disease:

- Lifestyle changes

- Medical treatment – drugs (e.g., cholesterol lowering medications, beta-blockers, nitroglycerin, calcium channel blockers, etc.);

- Coronary interventions as angioplasty and coronary stent;

- Coronary artery bypass grafting (CABG)

For patients in acute heart failure, ACE inhibitors, angiotensin receptor blockers, and beta blockers, are considered mainstays of heart failure treatment. But use of beta blockers specifically for takotsubo cardiomyopathy is controversial, because they may confer no benefit.

It is recommended that blood pressure typically be reduced to less than 140/90 mmHg. The diastolic blood pressure however should not be lower than 60 mmHg. Beta blockers are recommended first line for this use.

Drug therapy can slow down progression and in some cases even improve the heart condition. Standard therapy may include salt restriction, ACE inhibitors, diuretics, and beta blockers. Anticoagulants may also be used for antithrombotic therapy. There is some evidence for the benefits of coenzyme Q10 in treating heart failure.

Artificial pacemakers may be used in patients with intraventricular conduction delay, and implantable cardioverter-defibrillators in those at risk of arrhythmia. These forms of treatment have been shown to prevent sudden cardiac death, improve symptoms, and reduce hospitalization in patients with systolic heart failure.

The treatment of takotsubo cardiomyopathy is generally supportive in nature, for it is considered a transient disorder. Treatment is dependent on whether patients experience heart failure or acute hypotension and shock. In many individuals, left ventricular function normalizes within two months. Aspirin and other heart drugs also appear to help in the treatment of this disease, even in extreme cases. After the patient has been diagnosed, and myocardial infarction (heart attack) ruled out, the aspirin regimen may be discontinued, and treatment becomes that of supporting the patient.

While medical treatments are important to address the acute symptoms of Takotsubo cardiomyopathy, further treatment includes lifestyle changes. It is important that the individual stay physically healthy while learning and maintaining methods to manage stress, and to cope with future difficult situations.

Although the symptoms of Takotsubo cardiomyopathy usually go away on their own and the condition completely resolves itself within a few weeks, some serious complications can happen that must be treated. These most commonly include congestive heart failure and very low blood pressure, and less commonly include blood clotting in the apex of the left ventricle, irregular heart beat, and tearing of the heart wall.

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.

Depending on the type of cardiogenic shock, treatment involves infusion of fluids, or in shock refractory to fluids, inotropic medications. In case of an abnormal heart rhythm several anti-arrhythmic agents may be administered, e.g. adenosine.

Positive inotropic agents (such as dobutamine or milrinone), which enhance the heart's pumping capabilities, are used to improve the contractility and correct the low blood pressure. Should that not suffice an intra-aortic balloon pump (which reduces workload for the heart, and improves perfusion of the coronary arteries) or a left ventricular assist device (which augments the pump-function of the heart) can be considered. Finally, as a last resort, if the person is stable enough and otherwise qualifies, heart transplantation, or if not eligible an artificial heart, can be placed. These invasive measures are important tools- more than 50% of patients who do not die immediately due to cardiac arrest from a lethal abnormal heart rhythm and live to reach the hospital (who have usually suffered a severe acute myocardial infarction, which in itself still has a relatively high mortality rate), die within the first 24 hours. The mortality rate for those still living at time of admission who suffer complications (among others, cardiac arrest or further abnormal heart rhythms, heart failure, cardiac tamponade, a ruptured or dissecting aneurysm, or another heart attack) from cardiogenic shock is even worse around 85%, especially without drastic measures such as ventricular assist devices or transplantation.

Cardiogenic shock may be treated with intravenous dobutamine, which acts on β receptors of the heart leading to increased contractility and heart rate.

Restoring adequate blood flow to the heart muscle in people with heart failure and significant coronary artery disease is strongly associated with improved survival, some research showing up to 75% survival rates over 5 years. A stem cell study indicated that using autologous cardiac stem cells as a regenerative approach for the human heart (after a heart attack) has great potential.

American Heart Association practice guidelines indicate (ICD) implantable cardioverter-defibrillator use in those with ischemic cardiomyopathy (40 days post-MI) that are (NYHA) New York Heart Association functional class I. LVEF of >30% is often used to differentiate primary from ischemic cardiomyopathy, and a prognostic indicator. At the same time, people who undergo ventricular restoration on top of coronary artery bypass show improved postoperative ejection fraction as compared to those treated with only coronary artery bypass surgery. Severe cases are treated with heart transplantation.

After return of heart function, there has been a moderately higher risk of death in the hospital when compared to MI patients without PVF. Whether this still holds true with the recent changes in treatment strategies of earlier hospital admission and immediate angioplasty with thrombus removal is unknown. PVF does not affect the long-term prognosis.

Nitroglycerin can be used immediately to widen the coronary arteries and help increase blood flow to the heart. In addition, nitroglycerin causes peripheral venous and artery dilation reducing cardiac preload and afterload. These reductions allow for decreased stress on the heart and therefore lower the oxygen demand of the heart's muscle cells.

Antiplatelet drugs such as aspirin and clopidogrel can help reduce the progression of atherosclerotic plaque formation, as well as combining these with an anticoagulant such as a low molecular weight heparin.