Mortality, morbidity and evidence-based management amongst patients in regional New Zealand with severe left ventricular systolic dysfunction (1997-2011)

Abstract

Background: Heart failure and its management represents a significant health burden, the extent of which is poorly understood in regional New Zealand.

Aims: To investigate mortality, quality of life, hospitalisation, and evidence-based medical and device management of severe left ventricular (LV) systolic dysfunction in a regional New Zealand setting.

Methods: A retrospective case series was undertaken of 1126 patients with a LV ejection fraction <36% on transthoracic echocardiograms performed between 1 October 1997 and 31 March 2011 in Nelson Marlborough District Health Board. All-cause mortality and hospitalisation data were analysed for all participants. Substudies were undertaken regarding pharmacotherapy, demographics, implantable cardioverter-defibrillator implantation rates and quality of life based on the EQ-5D questionnaire and New York Heart Association class.

Results: Five-year cumulative survival was 44.5%. The mean annual medical admission rate was 204/100 000; 54.84% of which were readmissions in the same year. Prescription rates for angiotensin-converting enzyme inhibitors/angiotensin-receptor blockers, beta-blockers and spironolactone were 68.3%, 74.2% and 24.9%, respectively, with only 17.6%, 19.0% and 16.4% on maximum recommended doses. implantable cardioverter-defibrillator devices were inserted in 11.5% of eligible patients. Quality of life was impaired in patients <70 years relative to the age-approximated New Zealand index population. Mean EQ-5D visual analogue score was 72.6 ± 0.032 and self-reported New York Heart Association class 2.09 ± 0.107

Conclusion: Patients with severe LV systolic dysfunction in this regional New Zealand community experience similar mortality and first hospitalisation rates to those seen elsewhere in patients with clinical heart failure, but a greater number of readmissions. Medical and device therapy utilisation was suboptimal, and quality of life impaired, together supporting the need for a dedicated heart failure service.