Nasir Shariff

Health and Economic Outcomes Associated with Use of an Antimicrobial Envelope as a Standard of Care for Cardiac Implantable Electronic Device Implantation

Infection of cardiac implanted electrical devices (CIED) is a problem. In selected patients, use of an “antibacterial envelope” (AIGISRx®) is associated with low CIED infection rates. The value of this device when used as a standard of care is unclear.

Failure Rates of Single- Versus Dual-Coil Nonrecalled Sprint Quattro Defibrillator Leads

Electrical failure is more common in single-coil compared with dual-coil implantable cardioverter defibrillator (ICD) leads in the case of the recalled Riata lead. Single-coil leads are however favored in most patients given their lower risk of extraction. We therefore evaluated the failure-free survival of single- versus dual-coil ICD leads not included in Food and Drug Administration recalls. All patients receiving a Medtronic transvenous Sprint Quattro single- or dual-coil ICD lead were included in this analysis. Leads were followed to the end point of electrical failure. A total of 1,020 dual-coil and 631 single-coil ICD leads were implanted at our institution from November 2000 to March 2014. As expected, dual-coil leads had a longer follow-up time (3.4 ± 2.6 years vs 1.3 ± 1.0 years, p <0.001) because they were approved many years earlier by the Food and Drug Administration. The overall lead survival rates free from electrical failure at 1, 2, and 3 years after implantation were 98.8%, 98.2%, and 95.1%, respectively, for the single-coil leads versus 99.7%, 99.4%, and 99.3%, respectively, for the dual-coil leads (p = 0.0013). In conclusion, single-coil leads are associated with higher electrical failure rates compared with dual-coil leads even for nonrecalled lead models from the same family and manufacturer. These findings have implications on the choice of ICD lead at the time of device implantation.

Venous Thromboembolism in Patients with Heart Failure: In-hospital and Chronic Use of Anti-coagulants for Prevention

Heart failure (HF) is a common clinical syndrome characterized by high morbidity and frequent hospitalizations. HF is an independent and major risk factor for venous thromboembolism (VTE) and VTE occurring in patients with HF carries a worse prognosis. The present review will focus on short and long term role of anti-coagulants in prevention of venous thrombosis in HF patients. We will also be discussing the recently investigated and patented anti-coagulants which could have a role in this specific population.

Acute disseminated intravascular coagulation following ICD lead extraction.

We present an unusual case of disseminated intravascular coagulopathy (DIC) complicating percutaneous laser-assisted lead extraction. DIC has not been previously reported in association with lead extraction. It is possible to have occurred following the denudement of venous endothelium and exposure of underlying fibrous tissue. Practitioners need to be aware of this rare but potentially fatal complication of transvenous lead extraction.

Radiofrequency Ablation Improving LV Function in Cardiomyopathy Secondary to Low Burden of Premature Ventricular Complexes

A 58-year-old man presented with breathlessness and chest discomfort. Stress test demonstrated an area of ischemia in the inferolateral wall. Coronary angiogram showed a stenosis of left circumflex artery (LCA), which was stented. He was discharged on appropriate medications. At one-year follow-up, he had increasing breathlessness and palpitations. Electrocardiogram noted of sinus rhythm with PVCs (Fig.1). Echocardiogram showed an LV ejection fraction (EF) of 35% (60% a year prior). The LV end -systolic diameter (LVSD) was 4.9 cm and enddiastolic diameter (LVDD) was 6.1 cm. No other attributable causes for the deterioration such as alcohol abuse or viral illness were present. Holter monitor noted a PVC burden of 5120 (6%). Holter monitoring 2 months later noted a PVC burden of 9700 (11%). Coronary angiogram showed non-obstructive disease with patent stent. Considering the symptoms, PVC burden and reduction in LVEF, without an alternative etiology, a diagnosis of PVC induced cardiomyopathy was made. Medications used for PVCs in patients with heart failure and coronary disease are associated with worse outcome (1), a plan for RFA was taken. 3D reconstruction was performed with intracardiac echo Cartosound technique (Biosense Webster, Diamond Bar, CA). The PVC was targeted utilizing activation and pace mapping techniques. The best pace map was just below left main coronary artery in the left coronary cusp (Fig. 2). Angiogram was performed to identify the coronary arteries, to maintain safe distance of the ablation lesions. A 7F irrigated RFA catheter (Thermocool, Biosense Webster, Diamond Bar, CA) with 3.5 mm tip was used. RFA power was applied at 45 Watts with temperature control set at <40°C. The clinical PVC was terminated with the third lesion; two further ablations were delivered to secure complete ablation. At 1 month following the procedure, Holter study noted of only 6 PVCs. Echocardiogram showed LVEF of 50% with LVSD of 3.8 cm, and LVDD of 5.4 cm. One year since his ablation procedure, he has had remarkable improvement in his symptoms.

Impact of atrial fibrillation on long-term survival after cardiac valve surgery with or without coronary artery bypass

Background: Atrial fibrillation (AF) is the most common arrhythmia in patients undergoing cardiac valve surgery. AF in patients undergoing surgery can be categorized as preoperative AF (PPAF) or postsurgical AF (PSAF). Objective: To determine whether PSAF in patients undergoing valve surgery had an impact on mortality compared with patients in sinus rhythm or PPAF. Methods: A total of 556 consecutive patients who underwent valve surgery were reviewed. Patients were divided into three cohorts: sinus rhythm before and after surgery (n=293); PPAF (n=139); and sinus rhythm before and AF after the surgery (PSAF) (n=124). Baseline characteristics, surgical details and outcomes were recorded. Results: Compared with patients in sinus rhythm (mean [± SD] age 67.8±12.5 years), patients in the PPAF and PSAF groups were significantly older (73.1±9.9 years and 72.4±9.9 years, respectively). Hospital stay was significantly longer in the PPAF and PSAF groups (10.5±6.1 days and 11.3±8.3 days, respectively) compared with patients with sinus rhythm (7.12±4.9 days). During a follow-up of 51 months, all-cause mortality was significantly higher in both the PPAF and PSAF groups. This was irrespective of concomitant coronary bypass surgery. On multivariate Cox regression analysis, the adjusted risk for all-cause mortality for PPAF and PSAF was 1.93 (95% CI 1.18 to 3.17; P=0.01) and 1.64 (95% CI 1.07 to 2.53; P=0.02), respectively. Conclusion: Patients with PSAF and PPAF have longer hospital stays and higher long-term mortality rates than patients in sinus rhythm. Long-term mortality was similar between PPAF and PSAF.