Arrhythmias and cardiac MRI associations in patients with established cardiac dystrophinopathy.

AIMS: Some patients with cardiac dystrophinopathy die suddenly. Whether such deaths are preventable by specific antiarrhythmic management or simply indicate heart failure overwhelming medical therapies is uncertain. The aim of this prospective, cohort study was to describe the occurrence and nature of cardiac arrhythmias recorded during prolonged continuous ECG rhythm surveillance in patients with established cardiac dystrophinopathy and relate them to abnormalities on cardiac MRI. METHODS AND RESULTS: A cohort of 10 patients (36.3 years; 3 female) with LVEF<40% due to Duchenne (3) or Becker muscular (4) dystrophy or Duchenne muscular dystrophy-gene carrying effects in females (3) were recruited, had cardiac MRI, ECG signal-averaging and ECG loop-recorder implants. All were on standard of care heart medications and none had prior history of arrhythmias.No deaths or brady arrhythmias occurred during median follow-up 30 months (range 13-35). Self-limiting episodes of asymptomatic tachyarrhythmia (range 1-29) were confirmed in 8 (80%) patients (ventricular only 2; ventricular and atrial 6). Higher ventricular arrhythmia burden correlated with extent of myocardial fibrosis (extracellular volume%, p=0.029; native T1, p=0.49; late gadolinium enhancement, p=0.49), but not with LVEF% (p=1.0) on MRI and atrial arrhythmias with left atrial dilatation. Features of VT episodes suggested various underlying arrhythmia mechanisms. CONCLUSIONS: The overall prevalence of arrhythmias was low. Even in such a small sample size, higher arrhythmia counts occurred in those with larger scar burden and greater ventricular volume, suggesting key roles for myocardial stretch as well as disease progression in arrhythmogenesis. These features overlap with the stage of left ventricular dysfunction when heart failure also becomes overt. The findings of this pilot study should help inform the design of a definitive study of specific antiarrhythmic management in dystrophinopathy. TRIAL REGISTRATION NUMBER: ISRCTN15622536.

Arrhythmia prevalence and sudden death risk in adults with the m.3243A>G mitochondrial disorder.

AIMS: To define the prevalence of non-sustained tachyarrhythmias and bradyarrhythmias in patients with the m.3243A>G mitochondrial genotype and a previously defined, profile, associated with 'high sudden-death risk'. METHODS AND RESULTS: Patients at high risk of sudden death because of combinations of ventricular hypertrophy, mitochondrial encephalopathy, lactic acidosis and stroke-like episodes family phenotype, epilepsy or high mutation load, due to the m.3243A>G mutation, were identified from a mitochondrial cohort of 209 patients. All recruited had serial ECG and echo assessments previously according to schedule, had an ECG-loop recorder implanted and were followed for as long as the device allowed. Devices were programmed to detect non-sustained brady- or tachy-arrhythmias. This provided comprehensive rhythm surveillance and automatic downloads of all detections to a monitoring station for cardiology interpretation. Those with sinus tachycardia were treated with beta-blockers and those with ventricular hypertrophy received a beta-blocker and ACE-inhibitor combination.Nine consecutive patients, approached (37.2±3.9 years, seven males) and consented, were recruited. None died and no arrhythmias longer than 30s duration occurred during 3-year follow-up. Three patients reported palpitations but ECGs correlated with sinus rhythm. One manifest physiological, sinus pauses >3.5 s during sleep and another had one asymptomatic episode of non-sustained ventricular tachycardia. CONCLUSIONS: Despite 'high-risk' features for sudden death, those studied had negligible prevalence of arrhythmias over prolonged follow-up. By implication, the myocardium in this genotype is not primarily arrhythmogenic. Arrhythmias may not explain sudden death in patients without Wolff-Parkinson-White or abnormal atrioventricular conduction or, it must require a confluence of other, dynamic, proarrhythmic factors to trigger them.

Comparison of Sprint Fidelis and Riata defibrillator lead failure rates.

BACKGROUND/OBJECTIVES: Sprint Fidelis and Riata defibrillator leads are prone to early failure. Few data exist on the comparative failure rates and mortality related to lead failure. The aims of this study were to determine the failure rate of Sprint Fidelis and Riata leads, and to compare failure rates and mortality rates in both groups. METHODS: Patients implanted with Sprint Fidelis leads and Riata leads at a single centre were identified and in July 2012, records were reviewed to ascertain lead failures, deaths, and relationship to device/lead problems. RESULTS: 113 patients had Sprint Fidelis leads implanted between June 2005 and September 2007; Riata leads were implanted in 106 patients between January 2003 and February 2008. During 53.0 ± 22.3 months of follow-up there were 13 Sprint Fidelis lead failures (11.5%, 2.60% per year) and 25 deaths. Mean time to failure was 45.1 ± 15.5 months. In the Riata lead cohort there were 32 deaths, and 13 lead failures (11.3%, 2.71% per year) over 54.8 ± 26.3 months follow-up with a mean time to failure of 53.5 ± 24.5 months. There were no significant differences in the lead failure-free Kaplan-Meier survival curve (p=0.77), deaths overall (p=0.17), or deaths categorised as sudden/cause unknown (p=0.54). CONCLUSIONS: Sprint Fidelis and Riata leads have a significant but comparable failure rate at 2.60% per year and 2.71% per year of follow-up respectively. The number of deaths in both groups is similar and no deaths have been identified as being related to lead failure in either cohort.

Psychopathology in postinfarction patients implanted with cardioverter-defibrillators for secondary prevention. A cross-sectional, case-controlled study.

OBJECTIVE: To determine (1) the incidence of anxiety and depression in patients implanted with defibrillators for secondary arrhythmia protection after myocardial infarction; (2) the effect of comorbidity and receipt of shock therapy on psychosocial maladjustment. METHODS: Cross-sectional, one-off, questionnaire-based (HADS; MOS SF-36), case-controlled study of defibrillator recipients (n=100) from a 3-year implant period and three groups of matched controls [pacemaker (n=50), coronary intervention (n=50), atrial fibrillation (n=50)], sharing specific preselected previous health experiences. Spouses of each subgroup (n=106) were also studied. Although a cardiac rehabilitation program was available routinely for postinfarction patients, no specific rehabilitation was provided after defibrillator or pacemaker implant. RESULTS: Mean scores for each assessment were similar for each group. Individual patient scores, however, revealed similarly high incidences of anxiety (24-34%) and depression (14-22%) in all groups. Experience of implantable cardioverter-defibrillator (ICD) 'shock(s)' and 'shock storm(s)' (≥ 3 shocks in 24 h) increased anxiety significantly. HADS criteria for anxiety 'caseness' or borderline 'caseness' were met in 63.6% of shock-storm recipients. Abnormal anxiety scores did not differ with interval from index event. Individual HADS scores also identified high incidences of anxiety in all spouse groups (25-48%). CONCLUSIONS: Experience of shock storm precipitates pathological levels of anxiety in ICD recipients, and need for an ICD contributes to spouse anxiety. Individual CBT is indicated for patients who experience multiple shocks along with psycho-education for spouses. Anxiolytic and antidepressant medications may be indicated as part of their psychological rehabilitation.

Time to manual activation of implantable loop recorders--implications for programming recording period: a 10-year single-centre experience.

AIM: A new generation of commercially available implantable loop recorders (ILRs) has improved arrhythmia detection algorithms but reduced manually activated ECG storage duration. We investigated the effect that this would have had on symptom-arrhythmia correlation in a retrospective patient cohort. METHOD AND RESULTS: Retrospective review of all patients receiving a Medtronic Reveal 9525/9526 for the investigation of unexplained syncope or pre-syncope in our centre between 1998 and 2008. All ILRs were programmed for a single manual activation with 40 min retrospective ECG recording. We identified all patients who subsequently underwent permanent pacemaker implantation and analysed the time delay between bradycardia onset and manual ILR activation. Five hundred and sixty-four patients underwent implantation of an ILR during the study period. Of these, 57 (10%) subsequently underwent the implantation of a pacemaker (31 male, median age 66 years, range 9-86 years). In this group, 35 of 57 (61%) bradycardia diagnoses were made in patients (18 male, median age 65 years, range 9-86 years) after manual activation of the ILR. The median time from bradycardia onset to ILR activation was 136 s (0-488 s). Nineteen recordings showed high-grade atrio-ventricular block and 16 sinus node disease. CONCLUSION: Ten-year experience with the ILR confirms its utility in establishing a pacemaker indication as the cause for syncope or pre-syncope in 6% (34 of 564) of recipients following manual activation. This requires a recording loop of sufficient duration to reliably include both symptoms and activation.

Developing and implementing an HIV/AIDS educational curriculum for older adults.

PURPOSE: Recent data (2002) from the Centers for Disease Control and Prevention indicate that almost 11% of all cases of AIDS were diagnosed in people 50 and older. Despite the steady rise and future projections of increase, there is still a paucity of education and prevention programs targeting this population. This article reports on the development and piloting of an HIV/AIDS education prevention program. It describes an educational curriculum that provides older adults with accurate information about the relevance of HIV/AIDS to their lives. DESIGN AND METHODS: A purposive sample (n = 249) of ethnically and economically diverse adults 50 years and older was selected from 14 organizations in rural and urban settings in California. They were surveyed to determine their interest in participating in HIV/AIDS education prevention programs. RESULTS: A majority of participants reported interest in an HIV/AIDS prevention program for older people, with female respondents more likely to attend than male respondents. Participants who were moderately or very religious were also more likely to attend. Participants expressed preference for prevention education through presentations at centers serving older adults, and from physicians and other health care providers. On the basis of these findings, a specialized curriculum targeting older adults was developed, presented, and disseminated. IMPLICATIONS: People 50 years and older are sexually active, lack accurate information about HIV/AIDS, and are in need of HIV/AIDS education.

Evolution of ventricular function during permanent pacing from either right ventricular apex or outflow tract following AV-junctional ablation for atrial fibrillation.

AIMS: To compare acute and chronic ventricular function between patients, without cardiac failure, paced at either right ventricular apex or outflow tract. METHODS: Twenty patients. 10 paced apically and 10 in the outflow tract, underwent two radionuclide ventriculograms. Eight parameters of systolic or diastolic function were compared at each assessment, as were changes within each group over time. RESULTS: No differences were identified in systolic function between pacing sites 6 weeks after pacing or 23 weeks later. Peak filling rate was lower (P=0.04) at the second assessment with outflow tract pacing. No other diastolic differences were identified. Between assessments, time to peak filling rate prolonged (P=0.04) with apical pacing, while left ventricular area reduced (P=0.04) and peak filling rate decreased (P=0.04) with outflow tract pacing. Septal motion was better preserved with outflow tract pacing. No other parameter changed over time. ECG measures were similar at 14.7 months. CONCLUSIONS: No major differences were identified in systolic function between pacing sites. Some systolic parameters were better preserved with outflow tract pacing and diastolic function deteriorated subtly over time in both groups. Right ventricular pacing adversely affects left ventricular function.