While waiting for a defibrillator, a precordial thump may be attempted (However reserved to those who have the prior experience of doing so) in those on a heart monitor who are seen going into an unstable ventricular tachycardia. In those with cardiac arrest due to ventricular tachycardia, survival is about 45%. An implantable cardiac defibrillator or medications such as calcium channel blockers or amiodarone may be used to prevent recurrence. Signs and symptoms
While a few seconds may not result in problems, longer periods are dangerous. Short periods may occur without symptoms or present with lightheadedness, palpitations, or chest pain. Ventricular tachycardia may turn into ventricular fibrillation and can result in cardiac arrest. Cause
Ventricular tachycardia can occur due to coronary heart disease, aortic stenosis, cardiomyopathy, electrolyte problems (e.g., low blood levels of magnesium or potassium), inherited channelopathies (e.g., long-QT syndrome), catecholaminergic polymorphic ventricular tachycardia, arrhythmogenic right ventricular dysplasia, alcohol withdrawal syndrome (typically following atrial fibrillation), or a myocardial infarction. Pathophysiology
The morphology of the tachycardia depends on its cause and the origin of the re-entry electrical circuit in the heart.In monomorphic ventricular tachycardia, the shape of each heart beat on the ECG looks the same because the impulse is either being generated from increased automaticity of a single point in either the left or the right ventricle, or due to a reentry circuit within the ventricle. The most common cause of monomorphic ventricular tachycardia is scarring of the heart muscle from a previous myocardial infarction (heart attack).
A loop diuretic such as furosemide (or Lasix®) is administered, often together with morphine to reduce respiratory distress. Both diuretic and morphine may have vasodilator effects, but specific vasodilators may be used (particularly intravenous glyceryl trinitrate or ISDN) provided the blood pressure is adequate.Continuous positive airway pressure and bilevel positive airway pressure (CPAP/BiPAP) has been demonstrated to reduce mortality and the need of mechanical ventilation in people with severe cardiogenic pulmonary edema.It is possible for cardiogenic pulmonary edema to occur together with cardiogenic shock, in which the cardiac output is insufficient to sustain an adequate blood pressure to the lungs. This can be treated with inotropic agents or by intra-aortic balloon pump, but this is regarded as temporary treatment while the underlying cause is addressed and the lungs recover. == References ==