Ischemia acute cardiac disease

Eliminate the cause. Precipitating factors must be recognized and eliminated if possible. These include not only abnormalities of internal homeostasis, such as hypoxia or electrolyte abnormalities (especially hypokalemia or hypomagnesemia), but also drug therapy and underlying disease states such as hyperthyroidism or cardiac disease. It is important to separate this abnormal substrate from triggering factors, such as myocardial ischemia or acute cardiac dilation, which may be treatable and reversible. 

After administration of vinorelbine, chest pain occurs in up to 5% of patients. However, subsequent analysis showed that most patients had underlying cardiovascular disease or a tumor in the chest, making interpretation difficult (2,20). Three patients developed acute cardiopulmonary toxicity after vinorelbine therapy (25). The symptoms mimicked acute cardiac ischemia, but with no electrocardiographic changes or raised cardiac enzymes. In two patients, tachypnea, rales, wheezing, and severe dyspnea responded to inhaled salbutamol. One patient developed pulmonary edema and bilateral pleural effusions, which contained no malignant cells when drained. 

Regional ischemia in the course of atherosclerotic coronary artery disease is one of the most important causes of arrhythmia in the Western industrial world. These arrhythmias start with or often degenerate into ventricular fibrillation and are the main cause of sudden cardiac death in these countries. However, in the course of ischemia and infarction the mechanisms by which arrhythmia is induced vary with the duration of ischemia. In the acute phase of ischemia, i.e. within the first 2 1 h ventricular arrhythmias often occur. 

A retrospective analysis of postoperative renal function in patients undergoing cardiac operations has been conducted to evaluate whether the use of prophylactic intravenous diltiazem, in order to reduce the incidence of ischemia and dysrhythmias, was associated with increased renal dysfunction (10). The incidence of acute renal insufficiency requiring dialysis was 4.4% with diltiazem versus 0.7% in the controls. Logistic regression analysis suggested that the risk of acute renal insufficiency was strongly associated with intravenous diltiazem, age, baseline serum creatinine, the presence of left main coronary disease, and the presence of cerebrovascular disease. 

Peripheral arterial occlusion can be the initial manifestation of cardiac or systemic disease. At times, patients with chronic stable claudication may experience abrupt shortening of the distance at which claudication occurs, and this may be the only symptomatic evidence of an acute arterial occlusion either by embolization of by thrombus formation on a pre-existing arterial stenosis. The situation is not chronic and stable any more, but acute and unstable. As ischemia becomes more severe, the patient with chronic peripheral arterial disease develops ischemic pain at rest. The pathophysiologic mechanisms and the clinical presentation parallel the evolution of chronic stable angina pectoris to unstable angina and acute coronary syndromes. 

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