Multimorbidity and co-morbidity in atrial fibrillation and effects on survival: findings from UK Biobank cohort.

Aims: To examine the number and type of co-morbid long-term health conditions (LTCs) and their associations with all-cause mortality in an atrial fibrillation (AF) population. Methods and results: Community cohort participants (UK Biobank n = 502 637) aged 37-73 years were recruited between 2006 and 2010. Self-reported LTCs (n = 42) identified in people with AF at baseline. All-cause mortality was available for a median follow-up of 7 years (interquartile range 76-93 months). Hazard ratios (HRs) examined associations between number and type of co-morbid LTC and all-cause mortality, adjusting for age, sex, socio-economic status, smoking, and anticoagulation status. Three thousand six hundred fifty-one participants (0.7% of the study population) reported AF; mean age was 61.9 years. The all-cause mortality rate was 6.7% (248 participants) at 7 years. Atrial fibrillation participants with ≥4 co-morbidities had a six-fold higher risk of mortality compared to participants without any LTC. Co-morbid heart failure was associated with higher risk of mortality [HR 2.96, 95% confidence interval (CI) 1.83-4.80], whereas the presence of co-morbid stroke did not have a significant association. Among non-cardiometabolic conditions, presence of chronic obstructive pulmonary disease (HR 3.31, 95% CI 2.14-5.11) and osteoporosis (HR 3.13, 95% CI 1.63-6.01) was associated with a higher risk of mortality. Conclusion: Survival in middle-aged to older individuals with self-reported AF is strongly correlated with level of multimorbidity. This group should be targeted for interventions to optimize their management, which in turn may potentially reduce the impact of their co-morbidities on survival. Future AF clinical guidelines need to place greater emphasis on the issue of co-morbidity.

When to consider an implantable cardioverter defibrillator following myocardial infarction?

After reading this article the reader should be familiar with: Current guidelines for implantable cardioverter defibrillator (ICD) use post myocardial infarction (MI) and ischaemic cardiomyopathy. Primary prevention ICD guidelines. Secondary prevention ICD guidelines. Non-sustained ventricular tachycardia in patients post MI and the use of ICDs. Programming ICDs.

Interventricular lead separation is critical for NT-proBNP reduction after cardiac resynchronization therapy.

AIMS: Effective cardiac resynchronization therapy may depend upon the distance between left ventricular (LV) and right ventricular (RV) pacing leads. We assessed the influence of lead separation upon circulating NT-proBNP. MATERIALS & METHODS: In total, 132 patients underwent assessment, including NT-proBNP assay, before and after cardiac resynchronization therapy. 3D lead separation was calculated from postero-anterior and lateral chest radiography. RESULTS: Lead separation correlated with NT-proBNP reduction (r = 0.25; p = 0.004). Circulating NT-proBNP only fell in those with lead separation in the upper two quartiles. Deteriorating NT-proBNP occurred in 44 patients. Lead separation was less in these patients compared with those with an improvement (corrected 3D lead separation: 148.0 ± 5.38 and 170.5 ± 4.21 mm, respectively; p = 0.0018). CONCLUSION: Left ventricular-right ventricular lead separation correlates with postcardiac resynchronization therapy improvements in circulating NT-proBNP, a powerful marker of heart failure status and prognosis. Attention should be paid to achieving maximal lead separation at implantation.

Use of implantable cardioverter defibrillators in patients with left ventricular assist devices.

Patients with left ventricular assist devices (LVADs) are at high risk of sustained ventricular arrhythmias, but these may be remarkably well tolerated and the association with sudden death is unclear. Many patients who receive an LVAD already have an implantable cardioverter defibrillator (ICD). While it is standard practice to reactivate a previously implanted ICD in an LVAD recipient, this should include discussion of the revised risks and benefits of ICD therapy following LVAD implantation. In particular, patients should be warned that they might receive a significant number of ICD shocks that may not be life saving. When ICDs are reactivated, device programming should minimize the risk of repeated shocks for non-sustained or well-tolerated ventricular arrhythmias. Implantation of a primary prevention ICD after implantation of an LVAD is not supported by current evidence, poses potential risks, and should be the subject of a clinical trial before it becomes standard practice.

ICDs in end-stage heart failure.

Implantable cardioverter defibrillators (ICDs) reduce mortality in selected patients with chronic heart failure but prognostic benefit is likely to attenuate with progression to end-stage heart failure. The incidence of multiple futile ICD shocks before death is uncertain. Only individual patients, supported by their healthcare professionals, can decide when ICD therapy becomes futile in end-stage heart failure. Despite consensus that ICD deactivation should be routinely discussed, this rarely occurs in clinical practice for many reasons including uncertainty about when to initiate these discussions and reluctance to confront death and dying. Patient and carer opinions about end-stage heart failure and ICD deactivation may not meet professional expectations. Future research should focus on these opinions and examine interventions that bridge the gap between best practice and the reality of current clinical practice.

Radiofrequency ablation for persistent atrial fibrillation in patients with advanced heart failure and severe left ventricular systolic dysfunction: a randomised controlled trial.

OBJECTIVE: To determine whether or not radiofrequency ablation (RFA) for persistent atrial fibrillation in patients with advanced heart failure leads to improvements in cardiac function. SETTING: Patients were recruited from heart failure outpatient clinics in Scotland. DESIGN AND INTERVENTION: Patients with advanced heart failure and severe left ventricular dysfunction were randomised to RFA (rhythm control) or continued medical treatment (rate control). Patients were followed up for a minimum of 6 months. MAIN OUTCOME MEASURE: Change in left ventricular ejection fraction (LVEF) measured by cardiovascular MRI. RESULTS: 22 patients were randomised to RFA and 19 to medical treatment. In the RFA group, 50% of patients were in sinus rhythm at the end of the study (compared with none in the medical treatment group). The increase in cardiovascular magnetic resonance (CMR) LVEF in the RFA group was 4.5±11.1% compared with 2.8±6.7% in the medical treatment group (p=0.6). The RFA group had a greater increase in radionuclide LVEF (a prespecified secondary end point) than patients in the medical treatment group (+8.2±12.0% vs +1.4±5.9%; p=0.032). RFA did not improve N-terminal pro-B-type natriuretic peptide, 6 min walk distance or quality of life. The rate of serious complications related to RFA was 15%. CONCLUSIONS: RFA resulted in long-term restoration of sinus rhythm in only 50% of patients. RFA did not improve CMR LVEF compared with a strategy of rate control. RFA did improve radionuclide LVEF but did not improve other secondary outcomes and was associated with a significant rate of serious complications.

An entirely subcutaneous implantable cardioverter-defibrillator.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) prevent sudden death from cardiac causes in selected patients but require the use of transvenous lead systems. To eliminate the need for venous access, we designed and tested an entirely subcutaneous ICD system. METHODS: First, we conducted two short-term clinical trials to identify a suitable device configuration and assess energy requirements. We evaluated four subcutaneous ICD configurations in 78 patients who were candidates for ICD implantation and subsequently tested the best configuration in 49 additional patients to determine the subcutaneous defibrillation threshold in comparison with that of the standard transvenous ICD. Then we evaluated the long-term use of subcutaneous ICDs in a pilot study, involving 6 patients, which was followed by a trial involving 55 patients. RESULTS: The best device configuration consisted of a parasternal electrode and a left lateral thoracic pulse generator. This configuration was as effective as a transvenous ICD for terminating induced ventricular fibrillation, albeit with a significantly higher mean (+/-SD) energy requirement (36.6+/-19.8 J vs. 11.1+/-8.5 J). Among patients who received a permanent subcutaneous ICD, ventricular fibrillation was successfully detected in 100% of 137 induced episodes. Induced ventricular fibrillation was converted twice in 58 of 59 patients (98%) with the delivery of 65-J shocks in two consecutive tests. Clinically significant adverse events included two pocket infections and four lead revisions. After a mean of 10+/-1 months, the device had successfully detected and treated all 12 episodes of spontaneous, sustained ventricular tachyarrhythmia. CONCLUSIONS: In small, nonrandomized studies, an entirely subcutaneous ICD consistently detected and converted ventricular fibrillation induced during electrophysiological testing. The device also successfully detected and treated all 12 episodes of spontaneous, sustained ventricular tachyarrhythmia. (ClinicalTrials.gov numbers, NCT00399217 and NCT00853645.)

A prospective 1-year study of changes in neuropsychological functioning after implantable cardioverter-defibrillator surgery.

BACKGROUND: The testing of the implantable cardioverter-defibrillator (ICD), through the induction of repeated episodes of ventricular fibrillation, has been associated with disturbances in cerebral activity and increased levels of cytoplasmic enzymes. However, the neuropsychological outcomes of cerebral changes and their quality-of-life implications are unknown. METHODS AND RESULTS: Fifty-two ICD recipients completed standardized validated neuropsychological tests 1 to 3 days before ICD surgery and then 6 weeks, 6 months, and 12 months after surgery. They also completed psychometric tests measuring anxiety, depression, and quality of life. Between 31% and 39% of patients showed a significant neuropsychological impairment from their baseline function 6 weeks, 6 months, and 12 months after surgery. Ten percent of patients had late-onset deficits at 12 months only. Frequent areas of impairment were auditory and visual memory and attention. Neuropsychological impairment was not related to mood or quality of life at follow-up, although anxiety and depression predicted reduced quality of life. CONCLUSIONS: ICD implantation is associated with neuropsychological impairment that dissipates for the majority of recipients after 12 months. Short-term memory function and attention are particularly vulnerable to changes in oxygen during ICD testing. Although anxiety and depression are prevalent, there is little evidence for the direct impact of mood on cognition, and deficits appear not to be associated with reduced quality of life. These results provide evidence for longitudinal outcomes of ICD surgery and have implications for patient rehabilitation and adjustment.

Pre-ICD illness beliefs affect postimplant perceptions of control and patient quality of life.

BACKGROUND: The implantable cardioverter defibrillator (ICD) is a device used in the treatment of ventricular arrhythmias and the prevention of sudden cardiac death. However, the ICD has been associated with negative psychological outcomes such as anxiety, depression, panic, and poor quality of life (QoL). Recent studies suggest that the preimplantation psychology of patients, combined with their postimplantation perceptions about their cardiac condition, are greater contributory factors than their medical status to a poor outcome. METHOD: Our study employed an interview-based qualitative grounded theory methodology to explore whether medical history hetereogeneity and illness beliefs impact on the QoL of 13 ICD patients. RESULTS: Perceived control emerged as the core category related to QoL with three subsystem themes related to control: (1) illness beliefs, attributions, and appraisals; (2) coping resources and strategies; and (3) the social world. Patients at risk for the poorest adaptation were younger (<45), unemployed, and with an acute onset cardiac history. These patients interpreted their illness as severe, utilized emotion-focused coping (e.g., avoidance of situations), and believed themselves to be socially excluded. Adjusted patients used proactive problem-focused coping (e.g., normalizing) and minimized consequences of the device. CONCLUSIONS: The data developed a theoretical model of QoL, which identified perceived control, illness beliefs, and coping impacting on adjustment. From our study, we have a wider understanding of the combination psychological issues relevant to ICD patients and are able to treat those at risk with interventions to promote adjustment in the context of a society that values health and well-being.

A novel approach for a novel combination: a trans-septal biopsy of left atrial mass in recurrent phyllodes tumour.

A 69-year-old female with a previous hemisternectomy for recurrent phyllodes tumour was referred for echocardiography because of progressive dyspnoea, orthopnea, and a diastolic mitral rumble on auscultation. Transthoracic echocardiography revealed a large left atrial mass. Although a diagnosis of myxoma was likely, there was concern that this was a cardiac metastasis. A tissue diagnosis was mandatory before further thoracic surgery could be considered. This was obtained via a trans-septal puncture using transoesophageal echocardiographic guidance. Histology confirmed a diagnosis of myxoma, and our patient underwent successful surgery. This case highlights the importance of obtaining accurate tissue diagnosis and of excluding metastatic disease in patients with a cardiac mass and a history of tumour, prior to deciding whether surgical excision is warranted.

Paced ventricular electrogram fractionation predicts sudden cardiac death in hypertrophic cardiomyopathy.

AIMS: Paced electrogram fractionation analysis (PEFA) has been assessed for the prediction of sudden cardiac death (SCD) in a large-scale, prospective study of patients with hypertrophic cardiomyopathy (HCM). METHODS AND RESULTS: We determined the positive predictive value (PPV) of PEFA in relation to other risk factors for SCD and outcomes in 179 patients with HCM and no prior history of cardiac arrest. Patients were followed over a mean 4.3 years (range: 1.1-6.3 years). Thirteen patients had SCD-equivalent events: four of these patients died suddenly, three were resuscitated from ventricular fibrillation (VF), and six had implantable cardioverter-defibrillator (ICD) discharges in response to VF. PEFA identified nine of these patients and another 14 non-VF patients yielding a censored PPV of between 0.19 and 0.59 that was greater than the PPV that was the formal stopping point of the trial (0.18). Eighty per cent of patients were followed for 4 years or more. The PPV for the identification of SCD in this group was 0.38 (0.17-0.59). The use of two or more conventional markers to predict SCD identified five patients with SCD-equivalent events in the 4-year follow-up group and 42 other patients without events yielding a PPV of 0.106 (confidence limits 0.02-0.15). CONCLUSION: PEFA identifies HCM patients at risk of SCD with greater accuracy than non-invasive techniques and may have an important role in determining indications for ICD prescription.

Does treatment with ACE inhibitors or angiotensin II receptor antagonists prevent atrial fibrillation after dual chamber pacemaker implantation?

AIMS: A retrospective observational study was performed to test the hypothesis that a lower incidence of atrial fibrillation (AF) would be observed in patients treated with either angiotensin converting enzyme (ACE) inhibitors or angiotensin II receptor antagonists (AIIRAs) than those without these drugs, 1-year following implantation of a dual chamber pacemaker for all indications. METHODS: One hundred and sixty consecutive patients who underwent implantation of a dual chamber pacemaker between January and August 2002 were identified and their case notes were retrospectively analysed. The primary endpoint was the presence of persistent AF (confirmed by 12-lead ECG recorded from the visit to the pacemaker clinic) at 12-month follow-up. RESULTS: Overall, 8% patients developed new onset persistent AF at 1-year follow-up. The incidence of AF at 1-year was 4% in patients treated with ACE inhibitors, 8% in patients taking AIIRAs or 5% on either drug. Although a trend towards a higher incidence of AF was observed at 1-year (10%) in patients not receiving either of these drugs, this was not statistically significant (P = 0.21, drug vs. no drug). The incidence of AF in patients with a previous history of paroxysmal AF or cardioversion was significantly higher (23%) than those patients without (5%), P < 0.0001. An odds ratio (95% CI) of 7.9 (2.3-27.8) was obtained. CONCLUSION: To confirm these interesting initial results and to investigate this important relationship further, larger prospective randomised controlled studies are required.