Azam Shafquat

The gulf implantable cardioverter-defibrillator registry: Rationale, methodology, and implementation

Background: The implantable cardioverter-defibrillator (ICD) is effective in the prevention of sudden cardiac death in high-risk patients. Little is known about ICD use in the Arabian Gulf. We designed a study to describe the characteristics and outcomes of patients receiving ICDs in the Arab Gulf region. Methods: Gulf ICD is a prospective, multi-center, multinational, and observational study. All adult patients 18 years or older, receiving a de novo ICD implant and willing to sign a consent form will be eligible. Data on baseline characteristics, ICD indication, procedure and programing, in-hospital, and 1-year outcomes will be collected. Target enrollment is 1500 patients, which will provide adequate precision across a wide range of expected event rates. Results: Fifteen centers in six countries are enrolling patients (Saudi Arabia, United Arab Emirates, Kuwait, Oman, Bahrain, and Qatar). Two-thirds of the centers have dedicated electrophysiology laboratories, and in almost all centers ICDs are implanted exclusively by electrophysiologists. Nearly three-quarters of the centers reported annual ICD implant volumes of ≤150 devices, and pulse generator replacements constitute <30% of implants in the majority of centers. Enrollment started in December 2013, and accrual rate increased as more centers entered the study reaching an average of 98 patients per month. Conclusions: Gulf ICD is the first prospective, observational, multi-center, and multinational study of the characteristics and, the outcomes of patients receiving ICDs in the Arab Gulf region. The study will provide valuable insights into the utilization of and outcomes related to ICD therapy in the Gulf region.

Bioprosthetic tricuspid valve dysfunction in patients with transvalvular or epicardial pacing leads

Dysfunction of native tricuspid valves due to transvenous pacing leads is well described. Patients with bioprosthetic tricuspid valve (BTV) who need ventricular pacing are often advised epicardial lead placement to avoid potential damage to the BTV although there are no data to support this.

Increases in Heart Rate Variability Signal Improved Outcomes in Rapid Response Team Consultations: A Cohort Study

Background Reduced heart rate variability (HRV) indicates dominance of the sympathetic system and a state of “physiologic stress.” We postulated that, in patients with critical illness, increases in HRV might signal successful resuscitation and improved prognosis. Methods We carried out a prospective observational study of HRV on all patients referred to the rapid response team (RRT) and correlated with serial vital signs, lactate clearance, ICU admission, and mortality. Results Ninety-one patients were studied. Significantly higher HRV was observed in patients who achieved physiological stability and did not need ICU admission: ASDNN 19 versus 34.5, p=0.032; rMSSD 13.5 versus 25, p=0.046; mean VLF 9.4 versus 17, p=0.021; mean LF 5.8 versus 12.4, p=0.018; and mean HF 4.7 versus 10.5, p=0.017. ROC curves confirmed the change in very low frequencies at 2 hours as a strong predictor for ICU admission with an AUC of 0.772 (95% CI 0.633, 0.911, p=0.001) and a cutoff value of −0.65 associated with a sensitivity of 78.6% and a specificity of 61%. Conclusions Reduced HRV, specifically VLF, appears closely related to greater severity of critical illness, identifies unsuccessful resuscitation, and can be used to identify consultations that need early ICU admission.

Cardiac contractility modulation therapy: Are there superresponders?

Key Teaching Points • Heart failure is a common health care problem. • Patients with heart failure and narrow QRS complexes who are refractory to medical therapy represent a management challenge, as they are not candidates for cardiac resynchronization therapy. • Cardiac contractility modulation (CCM) therapy represents a promising therapeutic modality for these patients. • CCM is associated with increased maximal oxygen consumption and improved quality of life in patients with heart failure. • CCM may lead to left ventricular reverse remodeling, and it is expected to increase left ventricular ejection fraction (LVEF) by ~5%. • Patients with heart failure New York Heart Association functional class III and an LVEF of ≥25% respond exceptionally well to CCM therapy as suggested by subgroup analysis of large studies in this field.

Cardiac Contractility Modulation Device and Subcutaneous Implantable Cardioverter Defibrillator Combination: A New Hope for Heart Failure Patients with Low Ejection Fraction and Narrow QRS Complex

Background: Heart failure (HF) is a common cardiovascular disease with high rates of morbidity and mortality despite advances in medical and device-related management. Cardiac Contractility Modulation (CCM) is a promising therapy in HF patients with narrow QRS complex and CCM devices are approved and available for clinical use in Europe. On the other hand, there has recently been an increased interest in subcutaneous implantable cardioverter defibrillators (S-ICD) in HF patients with low ejection fraction. S-ICDs obviate the vascular and lead complications associated with conventional ICDs. There are limited data about the combination of CCM and S-ICD in management of HF patients.

Arrhythmogenic right ventricular cardiomyopathy/dysplasia in Saudi Arabia: a single-center experience with long-term follow-up.

BACKGROUND AND OBJECTIVES Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is a rare genetic disorder that primarily involves the right ventricle (RV). It is characterized by progressive replacement of RV myocardium by fibrofatty tissues. It commonly presents with ventricular tachycardia (VT) of RV origin and may result in RV failure. The aim of this study is to evaluate the clinical characteristics of adult patients with ARVC/D treated at the Heart Centre, King Faisal Specialist Hospital and Research Centre (KFSH&RC), Riyadh, Saudi Arabia. DESIGN AND SETTINGS This is a retrospective study of patients with ARVC/D diagnosed and treated at the KFSH&RC Heart Centre in Riyadh. PATIENTS AND METHODS Twenty-two cases with ARVC/D with regular follow-up at our Heart Centre from January 2007 to May 2010 were included in this study. The diagnosis of ARVC/D was made according to the revised International Task Force Criteria. The clinical data were collected from patients’ charts and electronic medical records. RESULTS The majority of patients were males (18; 82%). The diagnosis of ARVC/D was definite in 18 patients (82%), borderline in 2 (9%), and possible in 2 (9%). The mean age at diagnosis was 33.3 years. The follow-up period ranged from 29 to 132 months, with a mean follow-up period of 84 months. Ten patients presented with sustained VT, and 3 were survivors of cardiac arrest. Electrocardiogram abnormalities were present in 16/22 patients (72.7%). Echocardiographic changes meeting major diagnostic criteria were seen in 16 patients (76%). Cardiac magnetic resonance imaging was performed in 11 patients, and showed changes compatible with major diagnostic criteria in 7 patients (64%). Implantable cardioverter defibrillators (ICDs) were implanted in 17 patients; 8 had appropriate ICD shocks and 5 had inappropriate ICD shocks. Antitachycardia pacing was effective in terminating most of the VT/ventricular fibrillation episodes. CONCLUSION ARVC/D is a rare but increasingly recognized heart muscle disease seen in Saudi Arabia and other parts of the world. It is associated with a highly nonspecific presentation. VT of RV origin is a common presentation for this disease. Antiarrhythmic medications and ICD implantation are the main management options.