Clinical symptoms in patients with sustained ventricular tachycardia.

We questioned 113 patients with subsequently diagnosed sustained ventricular tachycardia (VT) regarding the symptoms that prompted their seeking hospital treatment, eliciting the following: 15% of patients had lost consciousness, 15% had near syncope, 35% had mild lightheadedness and 35% had no cerebral symptoms. Patients with preexisting congestive heart failure or a VT rate of 200 beats per minute or greater more often lost consciousness. Other symptoms included palpitations in 57% of patients, chest pain in 27%, dyspnea in 25%, weakness in 6%, nausea or diaphoresis in 3% each and flushing in 2%. In approximately 50% of patients who had mild lightheadedness or no cerebral symptoms, their condition was incorrectly diagnosed as supraventricular tachycardia based on the absence of severe symptoms during the tachycardia. In some patients, VT may be associated with mild or atypical symptoms. The differentiation of supraventricular from ventricular tachycardia should be based on electrocardiographic criteria and should not be influenced by the nature or severity of a patient's symptoms. The severity of cerebral symptoms is at least partially related to the VT rate and a patient's underlying heart disease.