Selected clinical features of paroxysmal tachycardia. A prospective study in 120 patients.

One hundred and twenty consecutive patients with paroxysmal tachycardia were personally evaluated in a prospective study. Some outstanding clinical features included the association of paroxysmal tachycardia and primary myocardial disease; the lack of palpitations in some patients with paroxysmal tachycardia; the relation of angina pectoris with paroxysmal tachycardia and coronary artery disease; the association of inferior and strictly posterior wall myocardial infarction with paroxysmal tachycardia; the unique presence of urina spastica in I9 2 per cent ofpatients; and the value of 'hunkering down' and sighing respiration in aborting attacks of rapid heart action. In addition, the role of precipitating factors in the onset of tachycardia and the finding that true paroxysmal atrial tachycardia ('PAT') appears to be an infrequent phenomenon when the entire group of paroxysmal arrhythmias is considered, have been presented. The relative ineffectiveness of digitalis, quinidine, and pronestyl has also been evaluated in a selected group of patients with frequent episodes of rapid heart action.