Michael Giudici

Comparison of Right Ventricular Outflow Tract and Apical Lead Permanent Pacing on Cardiac Output

Cardiac output was measured in 89 patients using transthoracic continuous-wave echo Doppler comparing right ventricular outflow tract pacing with the right ventricular apex at the time of permanent pacemaker implantation. Overall, cardiac output improved 18.8% (p <0.0001) and cardiac index 21.0% (p <0.0001) with outflow tract placement; patients with a lower baseline cardiac index had a greater percent improvement with outflow tract placement.

Submammary pacemakers and ICDs in women: long-term follow-up and patient satisfaction.

Background:  Device placement in women has unique considerations not addressed with standard implant techniques. These may include irritation and discomfort from purse and/or bra straps, changes in body image, and cosmetic issues with visible scars. Submammary device placement (SMI) addresses these problems and may be associated with greater patient comfort, cosmesis, and device acceptance.

Active-Can Implantable Cardioverter Defibrillator Placement from a Femoral Approach

This report describes a case of an active‐can ICD placed in the thigh. A 74‐year‐old man on chronic renal dialysis had no venous access from cephalic, subclavian, or jugular approaches. Using long active‐fixation leads the device was placed from a femoral approach with good sensing, pacing, and defibrillation parameters. (PACE 2003; 26:1297–1298)

Relation of 12-Lead Electrocardiogram Patterns to Implanted Defibrillator-Terminated Ventricular Tachyarrhythmias in Hypertrophic Cardiomyopathy

Electrocardiographic (ECG) abnormalities are common in hypertrophic cardiomyopathy (HC) and have been associated with the distribution of left ventricular hypertrophy and myocardial fibrosis. Such abnormalities may predispose patients to electrophysiologic instability, ventricular arrhythmias, and sudden cardiac death (SCD). We studied 330 patients with HC who were judged clinically to be at high risk for SCD and therefore received automatic implantable cardioverter-defibrillators (ICDs). Surface 12-lead electrocardiograms acquired at the time of ICD implantation were analyzed and the ECG characteristics of patients with appropriate device interventions for ventricular tachycardia and fibrillation were compared to those patients without appropriate device interventions. The 330 patients were followed for 3.7 +/- 3.0 years after implantation and 57 patients (17%) had appropriate discharges. No differences in the ECG characteristics of patients with and without appropriate device interventions were identified. Markedly increased ECG voltages, QRS duration, left or rightward QRS axis, abnormal Q waves, and QTc or QT dispersion were not associated with appropriate ICD discharge. Conversely, normal electrocardiograms and electrocardiograms normal except for a repolarization abnormality in only 1 anatomic distribution were not associated with freedom from ICD discharge. Moreover, no combination of ECG variables was associated with the likelihood of an appropriate ICD discharge. In conclusion, in a cohort of patients with HC selected because of their high risk for SCD, 12-lead surface electrocardiogram did not predict subsequent appropriate ICD intervention for ventricular tachyarrhythmias and was not useful in risk stratification for sudden death.

Electrocardiographic patterns during : Pacing the great cardiac and middle cardiac veins

Background: The electrocardiogram (ECG) patterns during pacing from the great cardiac vein (GCV) and the middle cardiac vein (MCV) are not well known.

Venous Stenosis After Transvenous Lead Placement: A Study of Outcomes and Risk Factors in 212 Consecutive Patients

Background Venous stenosis is a common complication of transvenous lead implantation, but the risk factors for venous stenosis have not been well defined to date. This study was designed to evaluate the incidence of and risk factors for venous stenosis in a large consecutive cohort. Methods and Results A total of 212 consecutive patients (136 male, 76 female; mean age 69 years) with existing pacing or implantable cardioverter-defibrillator systems presented for generator replacement, lead revision, or device upgrade with a mean time since implantation of 6.2 years. Venograms were performed and percentage of stenosis was determined. Variables studied included age, sex, number of leads, lead diameter, implant duration, insulation material, side of implant, and anticoagulant use. Overall, 56 of 212 patients had total occlusion of the subclavian or innominate vein (26%). There was a significant association between the number of leads implanted and percentage of venous stenosis (P =0.012). Lead diameter, as an independent variable, was not a risk factor; however, greater sum of the lead diameters implanted was a predictor of subsequent venous stenosis (P =0.009). Multiple lead implant procedures may be associated with venous stenosis (P =0.057). No other variables approached statistical significance. Conclusions A significant association exists between venous stenosis and the number of implanted leads and also the sum of the lead diameters. When combined with multiple implant procedures, the incidence of venous stenosis is increased.

Predictors of Long-term Maintenance of Normal Sinus Rhythm After Successful Electrical Cardioversion

Electrical cardioversion (EC) for atrial fibrillation (AF) is a common procedure performed in an attempt to restore normal sinus rhythm (NSR). Many factors predict long‐term maintenance of NSR and the risk of AF recurrence. The duration of AF, cardiac size and function, rheumatic heart disease, significant mitral valve disease, left atrial enlargement, and older age are among the most common recognized factors. A number of interventions can potentially decrease the AF recurrence rate. Identifying and treating reversible causes and the use of antiarrhythmic medications in certain situations can help decrease the risk of AF recurrence. The role of the newer anticoagulants is expanding, and wider application is expected in the near future. We hope that this summary will serve as a guide to physicians and healthcare providers to address the question of who should undergo cardioversion, as there are patients who are most likely to benefit from this procedure and others that will revert back into AF within a short period. To identify who would benefit most from EC and have a reasonable chance of long‐term maintenance of NSR, a thorough evaluation of each individual patient should be performed to tailor the best therapy to each individual.

Submammary Device Implantation in Women: A Step-by-Step Approach

Submammary Device Implantation in Women. Introduction: The frequency of device implantation is increasing in younger patients as our ability to diagnose long‐QT syndrome, hypertrophic cardiomyopathy, Brugada Syndrome, and other life‐threatening disorders earlier has improved. Similarly, use of cardiac resynchronization therapy and ICD therapies has increased in cardiomyopathy patients.

Sex-Specific Comparative Effectiveness of Oral Anticoagulants in Elderly Patients With Newly Diagnosed Atrial Fibrillation

Background— Sex-specific comparative effectiveness of direct oral anticoagulants among patients with nonvalvular atrial fibrillation is not known. Via this retrospective cohort study, we assessed the sex-specific, comparative effectiveness of direct oral anticoagulants (rivaroxaban and dabigatran), compared to each other and to warfarin among patients with atrial fibrillation. Methods and Results— Elderly (aged ≥66 years) Medicare beneficiaries enrolled in Medicare Part D benefit plan from November 2011 to October 2013 with newly diagnosed atrial fibrillation formed the study cohort (65 734 [44.8%] men and 81 137 [55.2%] women). Primary outcomes of inpatient admissions for ischemic strokes and major bleeding were compared across the 3 drugs (rivaroxaban: 20 mg QD, dabigatran: 150 mg BID, or warfarin) using 3-way propensity-matched samples. In men, rivaroxaban use decreased stroke risk when compared with warfarin use (hazard ratio, 0.69; 95% confidence interval, 0.48–0.99; P=0.048) and dabigatran use (hazard ratio, 0.66; 95% confidence interval, 0.45–0.96; P=0.029) and was associated with a similar risk of any major bleeding when compared with warfarin and dabigatran. In women, although ischemic stroke risk was similar in the 3 anticoagulant groups, rivaroxaban use significantly increased the risk for any major bleeding when compared with warfarin (hazard ratio, 1.20; 95% confidence interval, 1.03–1.42; P=0.021) and dabigatran (hazard ratio, 1.27; 95% confidence interval, 1.09–1.48; P=0.011). Conclusions— The reduced risk of ischemic stroke in patients taking rivaroxaban, compared with dabigatran and warfarin, seems to be limited to men, whereas the higher risk of bleeding seems to be limited to women.

Right ventricular septal pacing in patients with right bundle branch block.

BACKGROUND Cardiac resynchronization therapy (CRT) has been shown to improve left ventricular (LV) function and exercise performance in patients with left bundle branch block. Patients with right bundle branch block (RBBB) do not have a similar positive response to standard CRT. We hypothesized that single site pacing of the right ventricular septum (RVS) near the proximal right bundle could restore more normal activation of the LV in RBBB patients. METHODS 78 consecutive patients (56 M, 22 F) with baseline RBBB underwent pacemaker or ICD implantation. Leads were placed in the right atrium and RVS. RESULTS Baseline QRS duration was 120-220 ms (mean QRSd = 147 ms). At the optimal AV delay, the fused QRSd was 56-160 ms (mean QRSd = 112 ms). The mean decrease in QRSd was 34 ± 20.4 ms (p<0.001). CONCLUSION RVS pacing in patients with RBBB resulted in a marked decrease in QRS duration and often normalized the ECG.