Endocardial threshold of cardiac response as a function of electrode surface area

Synchronous Ventricular Pacing without Crossing the Tricuspid Valve or Entering the Coronary Sinus—Preliminary Results

“…In the present study, the helix was constructed with a 0.005 inch (platinum/iridium 90/10) wire, and the inner electrode was constructed with a 0.009 inch wire (MP 35N). The inner pin electrode (used as either anode or cathode) was insulated with 0.001 mm 2 polyamide tubing into which scalpel cuts were made to create electrode ports 15 . The lead was placed in the right ventricle (RV) on the septum approximately 1–2 cm proximal to the apex, close to the anticipated site of the right bundle branch exit, so as to closely mimic intrinsic LBBB ventricular activation.…”

“…Since the introduction of electrical stimulation therapy for symptomatic bradyarrhythmias, attempts have been made to identify the optimal site for pacing 1–3 . The most common ventricular pacing site is the right ventricular apex (RVA), which requires placing a lead across the tricuspid valve (TV).…”

“…Since the introduction of electrical stimulation therapy for symptomatic bradyarrhythmias, attempts have been made to identify the optimal site for pacing. [1][2][3] The most common ventricular pacing site is the right ventricular apex (RVA), which requires placing a lead across the tricuspid valve (TV). RVA pacing results in delayed left ventricular activation and can result in tricuspid regurgitation (TR), electromechanical dyssynchrony, and ventricular dysfunction.…”

“…RVA pacing results in delayed left ventricular activation and can result in tricuspid regurgitation (TR), electromechanical dyssynchrony, and ventricular dysfunction. [1][2][3][4][5][6] Cardiac resynchronization therapy (CRT) using a right ventricular lead and Authors Asirvatham, Johnson, Danielson, Friedman, and Bruce report a pending patent application on pacing lead technology by the Mayo Clinic. a left ventricular pacing lead has proved beneficial for patients with symptomatic congestive heart failure, depressed ventricular function, and left bundle branch block.…”

Reconstruction of Hyman's Second Pacemaker

“…No other US patent or application has been found. Neither the patent nor the subsequent manuscript provided sufficient information about the stimuli to allow comparison with what is now understood, to conclude whether they could actually stimulate the heart 8,9 . The published ECGs do not persuade (S. Furman) that a cardiac response actually occurred in response to a stimulus 10,12 …”