Abnormalities of cardiac rhythm and conduction can be lethal (sudden cardiac death), symptomatic (syncope, near syncope, dizziness, or palpitations), or asymptomatic. They are dangerous to the extent that they reduce cardiac output, so that perfusion of…

Coronary heart disease, or atherosclerotic coronary artery disease, is the commonest cause of cardiovascular disability and death in the United States. Men are more often affected than women by an overall ratio of 4:1,…

Congenital lesions account for only about 2% of heart disease that presents in adulthood. Only the most common acyanotic lesions are discussed here. The review articles cited below provide further discussion of the major…

While most cases of valvular disease in the United States were at one time due to rheumatic heart disease (still true in developing countries), other causes are now more common. The typical findings of…

The chest x-ray provides information about heart size, the pulmonary circulation (with characteristic signs suggesting both pulmonary artery or pulmonary venous hypertension), primary pulmonary disease, and aortic abnormalities. The echocardiogram provides much more reliable information…

A thorough physical examination can provide clues to the presence and severity of cardiovascular disease, and alert one to the presence of life-threatening conditions even before the results of any diagnostic…

Palpitations are the subjective awareness of the heart beating and are usually the result of a change in heart rate, heart rhythm, or the force of cardiac contraction.

Etiologies

A wide variety of disorders can…

Dyspnea is an uncomfortable awareness of breathing. It is a common symptom of cardiac and pulmonary diseases, and may also result from neurological conditions, chest wall problems, and anxiety states.

Differential Diagnosis of dyspnea (see…

History and Physical Examination
Despite major innovations in diagnostic technology and advances in medical therapy, a well-performed history and physical examination remain the cornerstone of good patient care. In addition to providing important clues…

Alveolar-arterial gradient = [(P_atm - P_H2O)(FIO₂) - (PCO₂/0.8)] - P_a02

Blood pressure = CO x SVR

CO = SV x HR (units: 1/min)

Chest Pain

• Angina
• Myocardial infarction
• Aortic dissection
• Pericarditis
• Pulmonary embolism
• Pneumonia
• Pleurisy
• Pneumothorax
• Pulmonary hypertension
• Gastroesophageal reflux disease
• Esophageal spasm
• Costochondritis
• Rib fracture
• Anxiety

A₂: aortic component of the second heart sound
ABE: acute bacterial endocarditis
ABI: ankle-brachial index
ACS: acute coronary syndrome
ACE: angiotensin-converting enzyme
AF: atrial…

7. Atrial Flutter
Atrial flutter is less common than fibrillation. It occurs most often in patients with COPD but may be seen also in those with rheumatic or coronary heart disease, congestive heart…

6. Atrial Fibrillation

Atrial fibrillation is the commonest chronic arrhythmia, with an incidence and prevalence that rise with age, so that it affects nearly 10% of individuals over age 80. It occurs in rheumatic…

A. Recurrent Paroxysmal Atrial Fibrillation
It is now well established that patients with recurrent paroxysmal atrial fibrillation are at similar stroke risk as those who are in atrial fibrillation chronically.…

5. Supraventricular Tachycardias Due to Accessory Atrioventricular Pathways (Preexcitation Syndromes)

Pathophysiology & Clinical Findings

Accessory pathways between the atria and the ventricle which avoid the conduction delay of the atrioventricular…

1. Sinus Arrhythmia, Bradycardia, & Tachycardia

Sinus arrhythmia is a cyclic increase in normal heart rate with inspiration and decrease with expiration. It results from reflex changes in vagal influence on the normal pacemaker and…

Susceptibility to arrhythmias results from genetic abnormalities (most often affecting ion channels) and acquired structural heart disease. Susceptibility may be increased by electrolyte abnormalities, hormonal imbalances (thyrotoxicosis, hypercatecholamine states), hypoxia, drug effects (such as…

Electrocardiographic Monitoring

The ideal way of establishing a causal relationship between a symptom and a rhythm disturbance is to demonstrate the presence of the rhythm during the symptom. Unfortunately, this is not…

Abnormalities of cardiac rhythm and conduction can be lethal (sudden cardiac death), symptomatic (syncope, near syncope, dizziness, or palpitations), or asymptomatic.

They are dangerous to the extent that they reduce cardiac…

A. Treatment of Acute Attack
Sublingual nitroglycerin is the drug of choice; it acts in about 1-2 minutes. Nitrates decrease arteriolar and venous tone, reduce preload and afterload, and lower the oxygen…

Indications
The indications for coronary artery revascularization in patients with angina pectoris are often debated. There is general agreement that otherwise healthy patients in the following groups should…

The prognosis of angina pectoris has improved with advances in the understanding of its pathophysiology and in pharmacologic therapy. Mortality rates vary depending on the number of vessels diseased, the severity of obstruction, the…

Although most symptoms of myocardial ischemia result from fixed stenosis of the coronary arteries or intraplaque hemorrhage or thrombosis at the site of lesions, some ischemic events may be…

Differential Diagnosis
Angina can usually be diagnosed from a proper history. When atypical features are present - such as prolonged duration (hours or days) or darting, knifelike pains at the apex…