Glucagonoma-associated dilated cardiomyopathy refractory to somatostatin analogue therapy.

A 67-year-old woman presented with a generalised rash associated with weight loss and resting tachycardia. She had a recent diagnosis of diabetes mellitus. Biochemical evaluation revealed elevated levels of circulating glucagon and chromogranin B. Cross-sectional imaging demonstrated a pancreatic lesion and liver metastases, which were octreotide-avid. Biopsy of the liver lesion confirmed a diagnosis of well-differentiated grade 2 pancreatic neuroendocrine tumour, consistent with metastatic glucagonoma. Serial echocardiography commenced 4 years before this diagnosis demonstrated a progressive left ventricular dilatation and dysfunction in the absence of ischaemia, suggestive of glucagonoma-associated dilated cardiomyopathy. Given the severity of the cardiac impairment, surgical management was considered inappropriate and somatostatin analogue therapy was initiated, affecting clinical and biochemical improvement. Serial cross-sectional imaging demonstrated stable disease 2 years after diagnosis. Left ventricular dysfunction persisted, however, despite somatostatin analogue therapy and optimal medical management of cardiac failure. In contrast to previous reports, the case we describe demonstrates that chronic hyperglucagonaemia may lead to irreversible left ventricular compromise. Management of glucagonoma therefore requires careful and serial evaluation of cardiac status. Learning points: In rare cases, glucagonoma may present with cardiac failure as the dominant feature. Significant cardiac impairment may occur in the absence of other features of glucagonoma syndrome due to subclinical chronic hyperglucagonaemia. A diagnosis of glucagonoma should be considered in patients with non-ischaemic cardiomyopathy, particularly those with other features of glucagonoma syndrome. Cardiac impairment due to glucagonoma may not respond to somatostatin analogue therapy, even in the context of biochemical improvement. All patients with a new diagnosis of glucagonoma should be assessed clinically for evidence of cardiac failure and, if present, a baseline transthoracic echocardiogram should be performed. In the presence of cardiac impairment these patients should be managed by an experienced cardiologist.

Device-identified atrial fibrillation at pacing clinics. Should it guide anticoagulation?

In recent years, there has been a significant increase in the number of devices implanted following improvement in their safety profile, extension of indications and reduction in cost. Although the reason remains largely the beneficial effect on heart rhythm stabilisation, implanted devices might also have additional advantages, notably identification of silent arrhythmia. Should clinicians therefore act on device-identified atrial fibrillation (AF) and should such identification be used to guide anticoagulation management? This review evaluates the current evidence on the management of device-identified asymptomatic AF.

Implantable cardioverter-defibrillator elective generator replacement: a procedure for all?

PURPOSE: Six risk stratification scores have been developed to estimate mortality risk in patients receiving an implantable cardioverter-defibrillator (ICD). This study aims at validating and comparing these risk scores in patients having elective ICD generator replacement (GR) and assessing the outcome of patients submitted to this procedure. METHODS: Two hundred twenty three consecutive patients with ischaemic or non-ischaemic dilated cardiomyopathy submitted to elective ICD GR and followed-up for 44 ± 19 months were included. We evaluated which of six previously developed risk scores could predict post-discharge all-cause mortality risk in this context with the highest efficacy. Comparisons between these scores were made using receiver-operating characteristic curves and the integrated discrimination improvement (IDI) index. We further assessed risk of appropriate ICD therapies and all-cause mortality following ICD GR. RESULTS: The prognostic utility of the six scores was assessed by calculating the AUC for follow-up all-cause mortality prediction: Goldenberg - 0.758 ± 0.042, p < 0.001; Parkash - 0.754 ± 0.042, p < 0.001; Bilchick - 0.813 ± 0.038, p < 0.001; Kraaier - 0.721 ± 0.043, p < 0.001; REPLACE DARE - 0.746 ± 0.048, p < 0.001; Providencia - 0.739 ± 0.043, p < 0.001. Through measures of risk reclassification (IDI and relative IDI), the score by Bilchick et al. was shown to outperform all other scores. Binary logistic regression identified pre-GR-appropriate ICD therapy as an independent predictor of post-GR ICD therapy (OR 6.2, CI 95% 3.0-12.7, p < 0.001), along with male gender (OR 6.6, CI 95% 0.8-55, p = 0.082) and history of atrial fibrillation (OR 2.28, CI 95% 1.1-4.5, p = 0.019). CONCLUSIONS: Current prediction scores are useful in predicting mortality risk of patients considered for ICD generator replacement and can potentially help identify patients who may not benefit from continuous ICD treatment due to high mortality rates regardless of the ICD.

Cardioverter-defibrillator implantation and generator replacement in the octogenarian.

AIMS: Increase in life expectancy has led to increased rate of implantable cardioverter-defibrillator (ICD) implantation in patients in their 80s, but there are no current formal recommendations to guide physicians when elderly patients with ICDs require elective unit replacement (EUR). This study aims at assessing survival and rates of ICD therapies in patients who have had ICD implantation or EUR above the age of 80, focusing on the latter. METHODS AND RESULTS: Retrospective analysis of a prospectively kept database of all ICD-related procedures carried out in a single tertiary centre. Patients 80 years of age or older submitted to ICD implantation (n = 42) or EUR (n = 34) between November 1991 and May 2012 were included. Using collected baseline and outcome data from this cohort, we assessed survival of these patients and the rates of ICD therapies. Median additional years of life after ICD implantation and ICD EUR in patients who died before data retrieval was 2.5 and 1.2, respectively, and while 65% of deceased patients after ICD implantation died in the first 3 years after the procedure, 50% of deceased post-ICD EUR patients died within the first year. Mortality rates at 1 and 2 years post-EUR were 23.1 and 38.1%, respectively. Furthermore, ventricular tachycardia occurred in a small minority of patients after EUR (16.7%) and no ventricular fibrillation-triggered ICD therapies were reported in both groups. CONCLUSION: In octogenarians who are due for an ICD EUR, careful thought should be given to the current clinical status, comorbidities, and general frailty prior to considering them for the procedure. A survival benefit from ICD EUR in this age stratum is not likely.