Leadless pacemaker perforations: Clinical consequences and related device and user problems.

Background: Cardiac perforation during leadless pacemaker implantation is more likely to require intervention than perforation by a transvenous lead. This study reports the consequences of Micra pacemaker perforations and related device and operator use problems based on information the manufacturer has submitted to the Food and Drug Administration (FDA).

Methods: FDA's Manufacturer and User Facility Device Experience (MAUDE) database was searched for Micra perforations.

Major adverse clinical events associated with implantation of a leadless intracardiac pacemaker.

Background: Leadless intracardiac pacemakers were developed to avoid the complications of transvenous pacing systems. The Medtronic Micra™ transcatheter pacemaker is one such system. We found an unexpected number of major adverse clinical events (MACE) in the Food and Drug Administration's Manufacturers and User Facility Device Experience (MAUDE) database associated with Micra implantation.

Reliability and longevity of implantable defibrillators.

Purpose: We hypothesized that data in manufacturers' product performance reports (PPRs) can provide clinically valuable ICD and cardiac resynchronization defibrillator (CRT-D) reliability and longevity information.

Methods: Data were obtained from 2019 PPRs. Kaplan-Meier (K-M) probabilities of freedom from malfunction, normal battery depletion (NBD), and NBD + malfunction were calculated for ICD and CRT-D pulse generators (PGs) with LiMnO2 or LiSVO/CFx batteries marketed in the USA from 2010 to 2019 and compared using the log-rank test.

Outcomes Before and After the Recall of a Heart Failure Pacemaker.

Importance: Timely and complete disclosure of medical device defects is necessary to manage patient care safely and effectively.

Objectives: To determine if the manufacturer's recommendations following the recall of a medical device were timely and complete, the follow-up information and data provided to patients and physicians were adequate for managing patient care, and the actions taken by the US Food and Drug Administration (FDA) regarding the recall were appropriate.

Design, Setting, And Participants: This single-center retrospective case series included 90 of 448 patients who were implanted with a cardiac resynchronization therapy pacemaker at the Minneapolis Heart Institute from May 2003 through January 2011; this pacemaker was recalled in November 2015.

High shocking and pacing impedances due to defibrillation lead calcification.

Purpose: We have reported the calcification of Endotak defibrillation leads that required replacement. The aim of this study was to assess calcified Endotak Reliance leads in the Food and Drug Administration Manufacturer and User Facility Device Experience (MAUDE) database and compare them to calcified Sprint Fidelis, Sprint Quattro Secure, Riata, and Durata leads in MAUDE.

Methods: We searched the MAUDE database from 2008 to 2019 for defibrillation lead calcification using the terms "calcium," "calcification," and "calcified".

Outcomes after pacemaker implantation in patients with new-onset left bundle-branch block after transcatheter aortic valve replacement.

New-onset left bundle branch block (N-LBBB) after transcatheter aortic valve replacement (TAVR) is a challenging clinical dilemma. In our single-center study, 60 out of 172 patients who underwent permanent pacemaker implantation (PPM) after TAVR had N-LBBB (34.9%).

Elevated T-wave alternans predicts nonsustained ventricular tachycardia in association with percutaneous coronary intervention in ST-segment elevation myocardial infarction (STEMI) patients.

Introduction: Successful reperfusion with primary percutaneous coronary intervention (PCI) can paradoxically elicit temporary vulnerability to ventricular arrhythmia. We examined whether T-wave alternans (TWA) level is correlated with nonsustained ventricular tachycardia (NSVT) incidence in association with PCI in patients with acute ST-segment elevation myocardial infarction (STEMI).

Methods And Results: We analyzed continuous 24-hour ambulatory electrocardiograms in 48 STEMI patients during and after successful primary PCI, achieving Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow.

Lead integrity alert algorithm decreases inappropriate shocks in patients who have Sprint Fidelis pace-sense conductor fractures.

Background: The Medtronic Sprint Fidelis high-voltage implantable cardioverter-defibrillator (ICD) lead is prone to fracture. The majority of fractures involve the pace-sense (P/S) conductors and may result in multiple inappropriate shocks. The Medtronic lead integrity alert (LIA) algorithm was designed to improve early detection of transient P/S conductor fractures and to decrease the incidence and number of inappropriate shocks.

Results of the Prospective Minnesota Study of ECHO/TDI in Cardiac Resynchronization Therapy (PROMISE-CRT) study.

Background: Retrospective single-center studies have shown that measures of mechanical dyssynchrony before cardiac resynchronization therapy (CRT), or acute changes after CRT, predict response better than QRS duration. The Prospective Minnesota Study of Echocardiographic/TDI in Cardiac Resynchronization Therapy (PROMISE-CRT) study was a prospective multicenter study designed to determine whether acute (1 week) changes in mechanical dyssynchrony were associated with response to CRT.

Methods And Results: Nine Minnesota Heart Failure Consortium centers enrolled 71 patients with standard indications for CRT.

Failure of impedance monitoring to prevent adverse clinical events caused by fracture of a recalled high-voltage implantable cardioverter-defibrillator lead.

Background: The Medtronic Sprint Fidelis implantable cardioverter-defibrillator high-voltage lead is prone to fracture. The October 2007 safety advisory recommended lead impedance monitoring to aid in identifying lead fractures.

Objective: The aim of this single-center study was to examine the effectiveness of impedance monitoring for detecting Sprint Fidelis lead failures before they caused adverse clinical events such as inappropriate shocks.

Microvolt T-wave alternans distinguishes between patients likely and patients not likely to benefit from implanted cardiac defibrillator therapy: a solution to the Multicenter Automatic Defibrillator Implantation Trial (MADIT) II conundrum.

Background: In 2003, the Centers for Medicaid and Medicare Services recommended QRS duration as a means to identify MADIT II-like patients suitable for implanted cardiac defibrillator (ICD) therapy. We compared the ability of microvolt T-wave alternans and QRS duration to identify groups at high and low risk of dying among heart failure patients who met MADIT II criteria for ICD prophylaxis.

Methods And Results: Patients with MADIT II characteristics and sinus rhythm had a microvolt T-wave alternans exercise test and a 12-lead ECG.

Unexpected loss of bipolar lead function associated with lead connection design in dual chamber pacemakers.

Unexpected loss of bipolar pacing function can occur in Guidant VIGOR dual chamber pacemakers with QC2 (Quick Connect) headers. In a retrospective review of 305 implanted patients, 23 exhibited unexpected loss of bipolar pacing lead function from < 1 to 51 months postimplant. Atrial lead problems were seen in 17 patients and ventricular lead problems in 6 (P < 0.