Myocarditis Acute inflammatory condition that can have an infectious, toxic or autoimmune etiology. Viral infections are the most common causes, such as Coxsackie and influenza A and B viruses. Myocarditis may occur several weeks after the initial viral symptoms and susceptibility is increased by corticosteroid treatment , immunosuppression, radiation, previous myocardial damage and exercise.

Clinical Features Diagnosis The clinical picture ranges from a symptomless disorder , sometimes recognized by the presence of an inappropriate tachycardia or abnormal ECG, to fulminant heart failure. Myocarditis may be heralded by an influenza like illness. Diagnosis - ECG changes are common but non-specific . - Biochemical markers of myocardial injury (e.g. troponin I and T, creatine kinase) are elevated. - Echocardiography may reveal left ventricular dysfunction , and if the diagnosis is uncertain it can be confirmed by endomyocardial biopsy. In most patients, the disease is self-limiting and only supportive therapy is available. the immediate prognosis is excellent . In most cases

Cardiomyopathy

Definition Cardiomyopathies are group of diseases primarily affecting the myocardium and characterized by myocardial dysfunction that is not the result of coronary atherosclerosis, hypertension, valvular dysfunction and pericardial abnormalities.

Types Dilated CMP Hypertrophic CMP Restrictive CMP Arrhythmogenic right ventricular cardiomyopathy. Obliterative cardiomyopathy.

Dilated (congestive) CMP Heart is enlarged and both ventricles are dilated. Myocardial contractility is diminished and cardiac output is reduced.

The pathogenesis is not clear Pathophysiology The pathogenesis is not clear

Etiology Idiopathic Familial (almost 20 %) Alcoholism (accounts for 15 to 40% of all cases ) Collagen vascular disease (SLE, rheumatoid Postmyocarditis Peripartum (last trimester of pregnancy or 5 m postpartum) Toxins (cobalt, lead, phosphorus Antiretroviral agents (zidovudine, didanosine, zalcitabine Infections: viral HIV, Coxsachivirus B, toxoplasmosis Hematologic (e.g., sickle cell anemia, hemochromatosis) Ischemic Nutritional (beri-beri) Irradiation

Symptoms Dyspnea on exertion Orthopnea, paroxysmal nocturnal dyspnea Asymptomatic Dyspnea on exertion Orthopnea, paroxysmal nocturnal dyspnea Fatigue Palpitations Systemic and pulmonary embolism Chest pain

Signs Raised JVP Small pulse pressure Resting tachycardia Raised JVP Small pulse pressure Pulmonary rales, hepatomegaly, peripheral edema S3, S4 MR,TR

Complications Congestive heart failure Arrhythmias ( brady or tachy) Thromboembolism Sudden cardiac death

Investigations Electrocardiogram( ECG) LBBB LVH with ST-T changes Arrhythmias (sinus tachycardia, AF, PVC, VT)

ECG

Chest X-Ray: cardiomegaly and pulmonary congestion Echocardiogram: Chamber enlargement and global hypokinesis

CXR

ECHO

Percutaneous Cardiac cath: Contrast left ventriculogram, coronary angiogram Endomyocardial biopsy: The role of endomyocardial biopsy in patients with dilated cardiomyopathy is not well defined.

Goals of therapy Treat underlying disease (SLE, alcoholism , hemochromatosis). Treat HF with sodium restriction, diuretics, ACE inhibitors , nitrates, β-blockers, spironolactone, and digitalis . Limit activity when CHF is present. Prevent thromboembolism with oral anticoagulants in all patients with Af and history thromboembolism.

Surgical treatment Patients with dilated cardiomyopathy (left ventricular EF <25%) and associated coronary atherosclerosis (angina, ECG changes, reversible defects on thallium scan) may benefit from surgical revascularization (CABG). Consider heart transplant for young patients (younger than 60 years of age) who are no longer responsive to medical therapy.

Hypertrophic cardiomyopathy This is the most common form of cardiomyopathy Genetic disorder, usually with autosomal dominant transmission

Types Obstructive 25 % Non obstructive The hypertrophy may be generalised or confined largely to the interventricular septum (asymmetric septal hypertrophy or other regions (e.g. apical hypertrophic cardiomyopathy)

Microscopically HCM is characterized by myocyte disarray in which there is loss of the normal parallel arrangement of cardiomyocytes, cells instead forming circles or whorls around foci of connective tissue. The myofibrillar architecture within cells is also disrupted (myofibrillar disarray).

Pathophysiology Diastolic dysfunction Myocardial ischemia Dynamic LV outflow tract obstruction ( atleast >30 mm, usually > 50mm Hg) Diastolic dysfunction Myocardial ischemia Mitral regurgitation Arrhythmias

Signs Double apex beat Palpable S4 Prominent “a” wave Apex localized, sustained Double apex beat Palpable S4 Prominent “a” wave Rapid upstroke carotid pulse, “jerky” bifid (spike- and-dome pulse) Harsh systolic ejection murmur at base MR: systolic murmur

ECG Pathologic Q waves, most commonly in the inferolateral leads. LA enlargement, Pathologic Q waves, most commonly in the inferolateral leads. Voltage criteria for LVH

ECG 1

ECHO Echocardiography is diagnostic

Treatment echocardiography/genetic counseling All first degree relatives: screening… echocardiography/genetic counseling Avoid competitive athletics Symptomatic Beta blockers or calcium channel blockers Antiarrythmic drugs Disopyramide or amoidarone

Invasive treatment High risk or non responders to medical treatment ICD ( high risk patients) DDD pacemaker Alcohol septal ablation Surgery Myectomy

Restrictive Cardiomyopathy (RCMP) Definition Restrictive cardiomyopathy is characterized by decreased ventricular compliance(stiff ventricles), usually secondary to infiltration of the myocardium. These patients have impaired ventricular filling and reduced diastolic volume, normal systolic function, and normal or near-normal myocardial thickness.

Amyloidosis is the most common cause in the UK, although other forms of infiltration (e.g. glycogen storage diseases) and a familial form of restrictive cardiomyopathy do occur. Diagnosis can be very difficult and requires complex Doppler echocardiography, CT or MRI, and endomyocardial biopsy. Treatment is symptomatic but the prognosis is usually poor and transplantation may be indicated.

Arrhythmogenic right ventricular cardiomyopathy In this condition, patches of the right ventricular myocardium are replaced with fibrous and fatty tissue . It is inherited as an autosomal dominant trait . The dominant clinical problems are ventricular arrhythmias, sudden death and right-sided cardiac failure. The ECG typically shows a slightly broadened QRS complex and inverted T waves in the right precordial leads. MRI is a useful diagnostic tool and is often used to screen the first-degree relatives of affected individuals. Patients at high risk of sudden death can be offered an ICD.