CASE REPORT Deterioration of Congestive Heart Failure after Converting to VOOMode from DDDMode in a Dilated Cardiomyopathy Patient; Importance of Atrial Contribution

Wedescribe a 62-year-old dilated cardiomyopathy patient in whomcongestive heart failure progressed shortly after DDDmodewas changed to VOOmode because of battery exhaustion. Emergency battery exchange with restoration of DDDmode improved his functional status to the previous level; pulmonary capillary wedge pressure decreased from 28 to 24 mmHgand cardiac output increased from 1.5 to 2.0 L/min associated with widening of the aortic pulse pressure. Maintenance of atrial contraction is therefore important even if left ventricular systolic function is markedly impaired and left ventricular end-diastolic pressure is increased. (Internal Medicine 32: 459-461, 1993)