স্পেশাল বিসিএস (স্বাস্থ্য) - লং কোর্স

Troponin I and troponin T are structural cardiac muscle proteins that are released during myocyte damage and necrosis, and represent the cornerstone of the diagnosis of acute myocardial infarction

Ref: Davidson P-393

The ECG shows normal but irregular QRS complexes; there are no P waves

There is a strong relationship between cigarette smoking and CAD, especially in younger (< 70 years) individuals, and this is the most important modifiable risk factor.

Chest pain at rest is the cardinal symptom of MI but breathlessness, vomiting and collapse are also common features. Painless or ‘silent’ MI may also occur and is particularly common in older patients or those with diabetes mellitus

The standard 12-lead ECG is central to confirming the diagnosis. The initial ECG may be normal or non-diagnostic in one-third of cases. Repeated ECGs are important, especially where the diagnosis is uncertain or the patient has recurrent or persistent symptoms. The earliest ECG change is usually ST-segment deviation.

These result from a combination of systolic and diastolic flow, such as occurs with a persistent ductus arteriosus, and must be distinguished from extracardiac noises such as bruits from arterial shunts, venous hums (high rates of venous flow in children) and pericardial friction rubs

Echocardiography is the definitive investigation and is helpful in monitoring the size of the effusion and its effect on cardiac function. The QRS voltages on the ECG are often reduced in the presence of a large effusion.

The BP is raised in the upper body but normal or low in the legs. The femoral pulses are weak and delayed in comparison with the radial pulse

Blood culture is the pivotal investigation to identify the organism that is the cause of the infection and to guide antibiotic therapy. Three to six sets of blood cultures should be taken prior to commencing therapy and should not wait for episodes of pyrexia. Echocardiography is key for detecting and following the progress of vegetations, for assessing valve damage and for detecting abscess formation

Staph. aureus has now overtaken streptococci as the most common cause of acute endocarditis. It originates from skin infections, abscesses or vascular access sites such as intravenous and central lines, or from intravenous drug use. 

The mitral valve is affected in more than 90% of cases; the aortic valve is the next most frequently involved, followed by the tricuspid and then the pulmonary valve

Physiological third heart sound: young people, pregnancy

Pathologicalthird heart sound: heart failure, mitral regurgitation

Sometimes cardiac failure can occur in patients without heart disease

due to a large arteriovenous shunt, or where there is an excessively high

cardiac output due to beri-beri, severe anaemia or thyrotoxicosis.

Angina pectoris is a symptom complex caused by transient myocardial ischaemia, which occurs whenever there is an imbalance between myocardial oxygen supply and demand. Coronary atherosclerosis is by far the most common cause of angina pectoris

ST elevation may signify myocardial infarction, pericarditis or left ventricular aneurysm
ST depression may signify ischaemia or infarction

Common abnormalities of the apex beat
Volume overload such as mitral or aortic regurgitation: displaced, thrusting
Pressure overload such as aortic stenosis, hypertension: discrete, heaving