The subcutaneous implantable cardioverter-defibrillator: Current trends in clinical practice between guidelines and technology progress

Work resumption after invasive heart procedures, rehabilitation and ergonomic evaluation: from the hospital to the workplace

Our Institute adopts a multidisciplinary protocol named "CardioWork" for work resumption after invasive cardiac procedures and subsequent rehabilitation: after evaluation of the cardiac functional profile, the occupational physician analyses the work activity prior to the cardiopathological event, identifies the presumed task energy requirement (from specific, published tables), and compares it with the exercise test results. Indications regarding timing and modality of returning to work are formulated accordingly. To verify the reliability of the indications thus provided, we carried out a clinical-functional follow-up study in the workplace, with Holter ECG and Armband measurement of actual energy expenditure. Over the course of two years, we enrolled 36 patients (mostly males, aged between 30 and 70 years), hospitalized after coronary revascularization, valve replacement or cardiac defibrillator implant. After rehabilitation, instrumental diagnostics (Holter ECG, echocardiography, exercise test) showed discrete functional conditions, with better values with regard to cardiac function than exercise capacity and effort tolerance. All subjects were judged fit for the job, in most cases with limitations concerning ergonomic factors, working timetable and/or stress. They returned to work quickly, with good adherence to the indications provided. Workplace Holter ECG did not show appreciable differences compared to the hospital evaluation. In one case, the average energy expenditure measured while working was higher than that inferred from the tables; in the remaining subjects, the actual expenditure coincided with what was expected or was lower. In a minority of cases (39%), the measured average expenditure slightly exceeded the optimal value (35% of the maximal value at the exercise test) recommended at the time of hospital discharge. At the end of the workplace evaluation, it was not necessary to formulate new indications. The study provides further evidence of the effectiveness of the CardioWork protocol in promoting return to work after invasive heart procedures. Though they need continuous updating, the published estimates of presumed task energy requirement remain reliable. In particularly complex cases, it is however advisable to carry out a field check of the ergometric assessments performed at the end of rehabilitation.

Air entrapment as a potential cause of early subcutaneous implantable cardioverter defibrillator malfunction: a systematic review of the literature

AIMS

Air entrapment (AE) has been reported as a potential cause of early inappropriate shocks (ISs) following subcutaneous implantable cardioverter defibrillator (S-ICD) implantation, but a cause-effect relationship is not always evident. This systematic review aims to analyse this phenomenon concerning implantation techniques, electrogram (EGM) features, radiologic findings, and patient management.

METHODS AND RESULTS

A systematic search was conducted using PubMed, Embase, and Google Scholar databases following the PRISMA guidelines to obtain all available literature data since 2010 on S-ICD malfunctions possibly due to AE. The final analysis included 54 patients with AE as a potential cause of S-ICD malfunction. Overall, the aggregate incidence of this condition was 1.2%. Of ICD malfunctions possibly due to AE, 93% were ISs, and 95% were recorded within the first week following implantation. Radiologic diagnosis of AE was confirmed in 28% of the entire study cohort and in 68% of patients in whom this diagnostic examination was reported. At the time of device malfunction, EGMs showed artefacts, baseline drift, and QRS voltage reduction in 95, 76, and 67% of episodes, respectively. Management included ICD reprogramming or testing, no action (observation), and invasive implant revision in 57, 33, and 10% of patients, respectively. No recurrences occurred during follow-up, irrespective of management performed.

CONCLUSIONS

Device malfunction possibly due to AE may occur in ∼1% of S-ICD recipients. Diagnosis is strongly suggested by early occurrence, characteristic EGM features, and radiologic findings. Non-invasive management, principally device reprogramming, appears to be effective in most patients.