Predictors of early mortality in patients age 80 and older receiving implantable defibrillators

Arrhythmias in Patients ≥80 Years of Age: Pathophysiology, Management, and Outcomes

Advances in medical care have led to an increase in the number of octogenarians and even older patients, forming an important and unique patient subgroup. It is clear that advancing age is an independent risk factor for the development of most arrhythmias, causing substantial morbidity and mortality. Patients ≥80 years of age have significant structural and electrical remodeling of cardiac tissue; accrue competing comorbidities; react differently to drug therapy; and may experience falls, frailty, and cognitive impairment, presenting significant therapeutic challenges. Unfortunately, very old patients are under-represented in clinical trials, leading to critical gaps in evidence to guide effective and safe treatment of arrhythmias. In this state-of-the-art review, we examine the pathophysiology of aging and arrhythmias and then present the available evidence on age-specific management of the most common arrhythmias, including drugs, catheter ablation, and cardiac implantable electronic devices.

Predictors for early mortality and arrhythmic events in patients with cardiac resynchronization therapy with defibrillator: A two center cohort study

BACKGROUND

Guidelines of heart failure therapy include cardiac resynchronization as standard of care in patients with severely depressed left ventricular function and wide QRS complex. It has been shown that patients benefit regarding mortality and morbidity. However, early mortality precludes longterm benefits from the device. The aim of the study was to identify predictors for early occurrence of both death and first-ever implantable cardioverter-defibrillator (ICD) therapy using a large combined database of patients with cardiac resynchronization therapy with defibrillator (CRT-D).

METHODS

From two registries (tertiary care centers) 904 patients were identified, no single patient was excluded. Early death was defined as death occurring within the 3 years after implantation whereas early ICD therapy as such occurring within the first year. 33 baseline parameters were compared using uni- and multivariate analysis with the Cox model and binary logistic regression.

RESULTS

The population was predominantly male (77%), with mean age of 63 ± 11 years and primary prevention indication in 80%. Mean follow-up was 55 ± 38 months. 256 (28%) patients had ICD therapies whereof the first-ever event occurred early in 52%. 270 (30%) patients died after 41 ± ± 31 months, mostly from advancing heart failure (41%), 141 (52%) patients of them early. Independent predictors for early ICD therapy were secondary prevention and renal failure. Independent predictors for early mortality were a history of percutaneous coronary intervention and of peripheral vascular disease.

CONCLUSIONS

Predictors for early mortality after CRT-D implantation were a history of percutaneous coronary intervention and peripheral vascular disease, present in only a minority of patients, thus limiting their use in clinical practice.

What is The Utility of Electrophysiological Study in Elderly Patients with Syncope and Heart Disease?

BACKGROUND

Syncope in elderly patients with heart disease is a growing problem. Its aetiological diagnosis is often difficult. We intended to investigate the value of the electrophysiological study (EPS) in old patients with syncope and heart disease.

METHODS

EPS was performed in 182 consecutive patients with syncope and heart disease, among whom 62 patients were ≥75 years old and 120 patients <75.

RESULTS

Left ventricular ejection fraction was 43.9±11.7% in patients ≥75 and 41.1±12.6% in patients <75. During EPS, induced sustained ventricular arrhythmias were as frequent in both groups (27.4% in patients ≥75 versus 27.5% in patients <75, p=0.99) whereas AV conduction abnormalities were more frequent in older patients (37.1% in patients ≥75 versus 18.3% in patients <75, p<0.005). Syncope remained unexplained in 35.5% of patients ≥75 and in 51.7% of patients <75 (p>0.04). ICD was more likely to be implanted in younger patients than in patients ≥75 years (37.5% vs 21% respectively, p<0.009). During a mean follow-up period of 3.3±3 years, the 4-year-survival rate was 66.9±6.8 % in patients ≥75 and 75.9±6.2 % in patients <75 years. The main cause of death was heart failure in both groups. The factors related to a worse outcome in a multivariate analysis were low LVEF and higher age.

CONCLUSION

Complete EPS allows the identification of treatable causes in a high proportion of elderly patients with syncope and heart disease. Yet, the prognosis of these patients is mainly related to LVEF and age.

Clinical and serum-based markers are associated with death within 1 year of de novo implant in primary prevention ICD recipients

BACKGROUND

Implantable cardioverter-defibrillator (ICD) implantation is contraindicated in those with <1-year life expectancy.

OBJECTIVES

The aim of this study was to develop a risk prediction score for 1-year mortality in patients with primary prevention ICDs and to determine the incremental improvement in discrimination when serum-based biomarkers are added to traditional clinical variables.

METHODS

We analyzed data from the Prospective Observational Study of Implantable Cardioverter-Defibrillators, a large prospective observational study of patients undergoing primary prevention ICD implantation who were extensively phenotyped for clinical and serum-based biomarkers. We identified variables predicting 1-year mortality and synthesized them into a comprehensive risk scoring construct using backward selection.

RESULTS

Of 1189 patients deemed by their treating physicians as having a reasonable 1-year life expectancy, 62 (5.2%) patients died within 1 year of ICD implantation. The risk score, composed of 6 clinical factors (age ≥75 years, New York Heart Association class III/IV, atrial fibrillation, estimated glomerular filtration rate <30 mL/min/1.73 m(2), diabetes, and use of diuretics), had good discrimination (area under the curve 0.77) for 1-year mortality. Addition of 3 biomarkers (tumor necrosis factor α receptor II, pro-brain natriuretic peptide, and cardiac troponin T) further improved model discrimination to 0.82. Patients with 0-1, 2-3, 4-6, or 7-9 risk factors had 1-year mortality rates of 0.8%, 2.7%, 16.1%, and 46.2%, respectively.

CONCLUSION

Individuals with more comorbidities and elevation of specific serum biomarkers were at increased risk of all-cause mortality despite being deemed as having a reasonable 1-year life expectancy. A simple risk score composed of readily available clinical data and serum biomarkers may better identify patients at high risk of early mortality and improve patient selection and counseling for primary prevention ICD therapy.

Changing nature of cardiac interventions in older adults

Older adults represent a rapidly growing segment of the population in developed countries. Advancing age is the most powerful risk factor for the development of cardiovascular disease (CVD), and CVD-related mortality increases markedly in older individuals. Procedures for patients with CVD, including percutaneous coronary intervention, aortic valve replacement and implantable cardioverter defibrillators were all initially validated in younger individuals but are increasingly being applied in older adults who for the most part have been significantly understudied in clinical trials. While advanced age alone is not a contraindication to these procedures, with the advent of less invasive methods to manage CVD including percutaneous techniques to treat both coronary artery disease and valvular heart disease, future research will need to weigh the potential harms of intervention in a population of older adults with multiple medical comorbidities and complex physiologic phenotypes against outcomes that include preventing functional decline and improving quality of life.