New insertable cardiac monitors show high diagnostic yield and good safety profile in real-world clinical practice: results from the international prospective observational SMART Registry.

AIMS: Insertable cardiac monitors (ICMs) are indicated for long-term monitoring of unexplained syncope or palpitations, and for detection of bradycardia, ventricular tachycardia, and/or atrial fibrillation (AF). The aim of our study was to evaluate the safety and clinical value associated with a new generation ICM (Confirm Rx™, Abbott, Illinois, USA), featuring a new remote monitoring system based on smartphone patient applications. METHODS AND RESULTS: The SMART Registry is an international prospective observational study. The main endpoints were ICM safety (incidence of serious adverse device and procedure-related events (SADEs) at 1 month), ICM clinical value (incidence of device-detected true arrhythmias and of clinical diagnoses and interventions), and patient-reported experience measurements (PREMs). A total of 1400 subjects were enrolled. ICM indications included syncope (49.1%), AF (18.8%), unexplained palpitations (13.6%), risk of ventricular arrhythmia (6.6%), and cryptogenic stroke (6.0%). Freedom from SADEs at 1 month was 99.4% (95% Confidence Interval: 98.8-99.7%). In the 6-month monitoring period, the ICM detected true cardiac arrhythmias in 45.7% of patients and led to clinical interventions in a relevant proportion of patients; in particular, a pacemaker implant was performed after bradycardia detection in 8.9% of subjects who received an ICM for syncope and oral anticoagulation therapy was indicated after AF detection in 15.7% of subjects with cryptogenic stroke. PREMs showed that 78.2% of subjects were satisfied with the remote monitoring patient app. CONCLUSION: The evaluated ICM is associated with an excellent safety profile and high diagnostic yield. Patients reported positive experiences associated with the use of their smartphone for the device remote monitoring.

Permanent His bundle pacing using a Biotronik stylet-driven Lead: feasibility and early outcomes from a single centre.

His bundle pacing (HBP) has been shown to be a good alternative to conventional cardiac resynchronisation therapy (CRT) and may theoretically provide an additional benefit where CRT has a response deficit of at least 30%. HBP requires mapping and identification of the His bundle, and to this purpose the lead delivery is challenging. This first-reported case series from Africa shares early experience with different pacing indications (complete heart block and pre-existing right ventricular pacing; heart failure with left bundle branch block) for using a standard 5.6F, Solia S 60, IS-1, ProMRI bipolar pacing lead and an 8.7F Selectra 3D introducer guide, 32-39-cm working length with 40/55/65-mm proximal radii (Biotronik). These cases highlighted the importance of appropriate programming when implanting HBP and of assessing the conduction system to predict patients who might benefit from HBP and additional left ventricular lead implant. The Biotronik Solia lead and delivery guide were found to be feasible and reliable in these cases. The Biotronik conduction system pacing tools were used with good acute outcomes in patients with different pacing indications.

Permanent Bi-Bundle Pacing in a Patient With Heart Failure and Left Bundle Branch Block.

Left bundle branch pacing (LBBP) is effective in patients with heart failure, left ventricular ejection fraction (LVEF) of ≤35%, and a widened QRS complex. LBBP leads to iatrogenic incomplete right bundle branch block (iRBBB). Bi-bundle pacing can resolve iRBBB, further narrowing the QRS duration, and may improve LVEF. (Level of Difficulty: Advanced.).

Cardiac Pacing Training in Africa: Endorsed by the Africa Heart Rhythm Association (AFHRA): JACC International.

The field of pacing in Africa has evolved in an uncoordinated way across the continent with significant variation in local expertise, cost, and utilization. There are many countries where pacemaker services do not meet one-hundredth of the national demand. Regional, national, and institutional standards for pacemaker qualification and credentials are lacking. This paper reviews the current needs for bradycardia pacing and evaluates what standards should be set to develop pacemaker services in a resource-constrained continent, including the challenges and opportunities of capacity building and training as well as standards for training programs (training prerequisites, case volumes, program content, and evaluation).

Pacemaker syndrome with sub-acute left ventricular systolic dysfunction in a patient with a dual-chamber pacemaker: consequence of lead switch at the header.

In the daily practice of pacemaker insertion, the occurrence of atrial and ventricular lead switch at the pacemaker box header is a rare and unintentional phenomenon, with less than five cases reported in the literature. The lead switch may have dire consequences, depending on the indication for the pacemaker. One of these consequences is pacemaker syndrome, in which the normal sequence of atrial and ventricular activation is impaired, leading to sub-optimal ventricular filling and cardiac output. It is important for the attending physician to recognise any worsening of symptoms in a patient who has recently had a permanent pacemaker inserted. In the case of a dual-chamber pacemaker, switching of the atrial and ventricular leads at the pacemaker box header should be strongly suspected. We present an unusual case of pacemaker syndrome and right ventricular-only pacinginduced left ventricular systolic dysfunction in a patient with a dual-chamber pacemaker.

Anticoagulation bridging around device surgery: compliance with guidelines.

BACKGROUND: Current guidelines recommend bridging anticoagulation in patients undergoing cardiac rhythm device surgery with a "moderate to high risk" of thromboembolism. Patients at "low risk" are advised to stop oral anticoagulation without bridging to the procedure. This study examines real world adherence to accepted guidelines and the clinical sequelae of nonadherence. METHODS: We performed a review of all patients undergoing device surgery receiving chronic anticoagulation over a prespecified time period of 14 months. Patients were classified per American College of Chest Physician guidelines as "moderate/high risk" or "low risk" of thromboembolism. We then compared perioperative management of anticoagulation to guideline recommendations and assessed the rate of perioperative bleeding and thromboembolism. RESULTS: One hundred and twenty-nine patients were included in this study. Sixty-two (48%) were classified as "moderate/high risk" and 67 (52%) "low risk." In the "moderate/high risk" group 47/62 (76%) received perioperative anticoagulation but only 25/62 (40%) were bridged both pre- and postprocedure or maintained on uninterrupted warfarin. In the "low risk" group, 22/67 (33%) received bridging therapy. Device pocket hematoma or perioperative bleeding occurred in 10/129 (8%) with 4/10 receiving inappropriate bridging for a calculated low risk of thromboembolism. There were no perioperative thromboembolisms. CONCLUSIONS: Our study identified significant underutilization of bridging, particularly in the postoperative period, in patients at "moderate/high risk" of thromboembolism. Conversely, bridging was overused in "low risk" patients and associated with bleeding complications. Physicians should be urged to follow current expert guidelines in regard to bridging anticoagulation for cardiac rhythm device surgery. (PACE 2012;35:1480-1486).

Predictors of fracture risk of a small caliber implantable cardioverter defibrillator lead.

INTRODUCTION: The Sprint Fidelis 6949 implantable cardioverter defibrillator (ICD; Medtronic Inc., Minneapolis, MN, USA) lead has a high rate of fracture. Identification of predictors of subsequent fracture is useful in decision making about lead replacement and for future lead design. We sought to determine if there are clinical, procedural, or radiological features associated with a greater risk of subsequent lead fracture. METHODS: Patients with Sprint Fidelis 6949 lead fractures (Fracture group) were identified from our institutional database. Each patient in the Fracture group was matched to two controls, immediately preceeding and succeeding Sprint Fidelis 6949 implant. Clinical and procedural characteristics were compared. Chest radiographs performed 2 weeks after ICD implant were reviewed by an observer blinded to outcomes. The following features were assessed: ICD tip location, lead slack, kinking of the lead body (> or =90 degrees ), and presence of lead "crimping" within the anchoring sleeve. RESULTS: Twenty-six patients with Sprint Fidelis 6949 lead fractures were identified and were matched to 52 control patients. On univariate analysis, a higher left ventricular ejection fraction (LVEF), prior ipsilateral device implant, history of prior ICD lead fracture, and noncephalic venous access were associated with risk of lead fracture. On multivariate analysis, a higher LVEF was the only independent predictor of lead fracture (P = 0.006). Radiological features were similar between the two groups. CONCLUSIONS: In this study, a higher LVEF was associated with a greater risk of lead fracture in patients with Sprint Fidelis 6949 ICD leads. Radiographic features did not predict subsequent risk of lead fracture in our population. (PACE 2010; 437-443).

Clinical features, survival experience, and profile of plakophylin-2 gene mutations in participants of the arrhythmogenic right ventricular cardiomyopathy registry of South Africa.

Little is known about arrhythmogenic right ventricular cardiomyopathy (ARVC) in Africa. The objective of this study was to delineate the clinical characteristics, survival, and genetics of ARVC in South Africa. Information on clinical presentation, electrocardiographic and cardiac imaging findings, histology, and outcome of cases with suspected ARVC was collected using the standardised form of the ARVC Registry of South Africa. Genomic DNA was screened for mutations in plakophylin-2 (PKP2) gene. Survival and its predictors were analyzed using the Kaplan-Meier and Cox proportional hazards regression methods, respectively. Fifty unrelated cases who met the diagnostic criteria for ARVC were enrolled between January 2004 and April 2009. Clinical presentation was similar to that reported in other studies. Annual mortality rate was 2.82%, five-year cumulative mortality rate 10%, and mean age at death 36.9 +/- 14.7 years. Overall survival was similar to the general South African population (P = 0.25). Independent risk factors for death were syncope (Hazard Ratio [HR] 10.73, 95% Confidence Interval [CI] 1.88-61.18, P = 0.008) and sustained ventricular tachycardia (HR = 22.97, 95%CI 2.33-226.18, P = 0.007). Seven PKP2 gene mutations were found in 9/36 (25%) unrelated participants, five being novel. The novel C1162T mutation occurred in four white South Africans sharing a common haplotype, suggesting a founder effect. Compound heterozygotes exhibited a severe phenotype signifying an allele dose effect. ARVC is associated with early mortality that is no different to the general South Africa population whose lifespan is shortened by HIV/AIDS. PKP2 gene mutations are common, have an allele dose effect, and a novel founder effect in white South Africans.

Mortality in patients treated for tuberculous pericarditis in sub-Saharan Africa.

OBJECTIVE: To determine the mortality rate and its predictors in patients with a presumptive diagnosis of tuberculous pericarditis in sub-Saharan Africa. DESIGN: Between 1 March 2004 and 31 October 2004, we enrolled 185 consecutive patients with presumed tuberculous pericarditis from 15 referral hospitals in Cameroon, Nigeria and South Africa, and observed them during the 6-month course of antituberculosis treatment for the major outcome of mortality. This was an observational study, with the diagnosis and management of each patient left at the discretion of the attending physician. Using Cox regression, we have assessed the effect of clinical and therapeutic characteristics (recorded at baseline) on mortality during follow-up. RESULTS: We obtained the vital status of 174 (94%) patients (median age 33; range 14 - 87 years). The overall mortality rate was 26%. Mortality was higher in patients who had clinical features of HIV infection than in those who did not (40% v. 17%, p=0.001). Independent predictors of death during followup were: (i) a proven non-tuberculosis final diagnosis (hazard ratio (HR) 5.35, 95% confidence interval (CI) 1.76 - 16.25), (ii) the presence of clinical signs of HIV infection (HR 2.28, CI 1.14 - 4.56), (iii) coexistent pulmonary tuberculosis (HR 2.33, CI 1.20 - 4.54), and (iv) older age (HR 1.02, CI 1.01 - 1.05). There was also a trend towards an increase in death rate in patients with haemodynamic instability (HR 1.80, CI 0.90 - 3.58) and a decrease in those who underwent pericardiocentesis (HR 0.34, CI 0.10 - 1.19). CONCLUSION: A presumptive diagnosis of tuberculous pericarditis is associated with a high mortality in sub-Saharan Africa. Attention to rapid aetiological diagnosis of pericardial effusion and treatment of concomitant HIV infection may reduce the high mortality associated with the disease.

Clinical characteristics and initial management of patients with tuberculous pericarditis in the HIV era: the Investigation of the Management of Pericarditis in Africa (IMPI Africa) registry.

BACKGROUND: The incidence of tuberculous pericarditis has increased in Africa as a result of the human immunodeficiency virus (HIV) epidemic. However, the effect of HIV co-infection on clinical features and prognosis in tuberculous pericarditis is not well characterised. We have used baseline data of the Investigation of the Management of Pericarditis in Africa (IMPI Africa) registry to assess the impact of HIV co-infection on clinical presentation, diagnostic evaluation, and treatment of patients with suspected tuberculous pericarditis in sub-Saharan Africa. METHODS: Consecutive adult patients in 15 hospitals in three countries in sub-Saharan Africa were recruited on commencement of treatment for tuberculous pericarditis, following informed consent. We recorded demographic, clinical, diagnostic and therapeutic information at baseline, and have used the chi-square test and analysis of variance to assess probabilities of significant differences (in these variables) between groups defined by HIV status. RESULTS: A total of 185 patients were enrolled from 01 March 2004 to 31 October 2004, 147 (79.5%) of whom had effusive, 28 (15.1%) effusive-constrictive, and 10 (5.4%) constrictive or acute dry pericarditis. Seventy-four (40%) had clinical features of HIV infection. Patients with clinical HIV disease were more likely to present with dyspnoea (odds ratio [OR] 3.2, 95% confidence interval [CI] 1.4 to 7.4, P = 0.005) and electrocardiographic features of myopericarditis (OR 2.8, 95% CI 1.1 to 6.9, P = 0.03). In addition to electrocardiographic features of myopericarditis, a positive HIV serological status was associated with greater cardiomegaly (OR 3.89, 95% CI 1.34 to 11.32, P = 0.01) and haemodynamic instability (OR 9.68, 95% CI 2.09 to 44.80, P = 0.0008). However, stage of pericardial disease at diagnosis and use of diagnostic tests were not related to clinical HIV status. Similar results were obtained for serological HIV status. Most patients were treated on clinical grounds, with microbiological evidence of tuberculosis obtained in only 13 (7.0%) patients. Adjunctive corticosteroids were used in 109 (58.9%) patients, with patients having clinical HIV disease less likely to be put on them (OR 0.37, 95% CI 0.20 to 0.68). Seven patients were on antiretroviral drugs. CONCLUSION: Patients with suspected tuberculous pericarditis and HIV infection in Africa have greater evidence of myopericarditis, dyspnoea, and haemodynamic instability. These findings, if confirmed in other studies, may suggest more intensive management of the cardiac disease is warranted in patients with HIV-associated pericardial disease.