PAROXYSMAL HEART BLOCK AND VENTRICULAR STANDSTILL

Paroxysmal Ventricular Standstill: A Rare Cardiac Manifestation of Syncope

Patient: Male, 40-year-old

Final Diagnosis: Ventricular standstill

Symptoms: Seizure-like activity

Medication: —

Clinical Procedure: —

Specialty: Cardiology

Elusive cardiac dysrhythmia in high-risk syncope

Emergency department presentations of syncope can vary from benign to life-threatening etiologies. Older patients are at increased risk of cardiac causes of syncope. Ventricular standstill is a rare phenomenon that can manifest as syncope and must be correctly identified and promptly treated to prevent sudden cardiac arrest. We report the case of a 70-year old man with dizziness and convulsive syncope whose initial ECG showed a right bundle branch block, but then developed ventricular standstill and intermittent high-grade AV block while still in the ED. He was transferred to the ICU and underwent pacemaker implantation. A high index of suspicion for dysrhythmias should be maintained for any patient presenting to the ED with high-risk syncope.

Remission and recovery from chronic, established, complete heart block

The return of A-V conduction is described in a patient after two decades of high-grade or complete congenital heart block. Similar cases have been reported by others, with remission or even recovery commencing up to the fourth decade or later. A similar phenomenon is also described in four patients with acquired heart block of four to ten years' duration; in them, remission was usuallly brief but persisted for seven years in one patient. No full report of this seems to have been published previously. Possible explanations are discussed, but no conclusion is reached. Apart from its interest, the phenomenon is of importance with respect to the selection of demand-type electronic pacemakers in the management of patients with heart block.