Impact of the number of comorbidities on cardiac sympathetic derangement in patients with reduced ejection fraction heart failure

Cardiac sympathetic innervation and mortality risk scores in patients with heart failure

INTRODUCTION

In the risk stratification and selection of patients with heart failure (HF) eligible for implantable cardioverter-defibrillator (ICD) therapy, ¹²³ I-meta-IodineBenzylGuanidine (¹²³ I-mIBG) scintigraphy has emerged as an effective non-invasive method to assess cardiac adrenergic innervation. Similarly, clinical risk scores have been proposed to identify patients with HF at risk of all-cause mortality, for whom the net clinical benefit of device implantation would presumably be lower. Nevertheless, the association between the two classes of tools, one suggestive of arrhythmic risk, the other of all-cause mortality, needs further investigation.

OBJECTIVE

To test the relationship between the risk scores for predicting mortality and cardiac sympathetic innervation, assessed through myocardial ¹²³ I-mIBG imaging, in a population of patients with HF.

METHODS

In HF patients undergoing ¹²³ I-mIBG scintigraphy, eight risk stratification models were assessed: AAACC, FADES, MADIT, MADIT-ICD non-arrhythmic mortality score, PACE, Parkash, SHOCKED and Sjoblom. Cardiac adrenergic impairment was assessed by late heart-to-mediastinum ratio (H/M) <1.6.

RESULTS

Among 269 patients suffering from HF, late H/M showed significant negative correlation with all the predicting models, although generally weak, ranging from -0.15 (p = .013) for PACE to -0.32 (p < .001) for FADES. The scores showed poor discrimination for cardiac innervation, with areas under the curve (AUC) ranging from 0.546 for Parkash to 0.621 for FADES.

CONCLUSION

A weak association emerged among mortality risk scores and cardiac innervation, suggesting to integrate in clinical practice tools indicative of both arrhythmic and general mortality risks, when evaluating patients affected by HF eligible for device implantation.

123I-MIBG imaging in heart failure: impact of comorbidities on cardiac sympathetic innervation

PURPOSE

Heart failure (HF) is a primary cause of morbidity and mortality worldwide, with significant impact on life quality and extensive healthcare costs. Assessment of myocardial sympathetic innervation function plays a central role in prognosis assessment in HF patients. The aim of this review is to summarize the most recent evidence regarding the clinical applications of iodine-123 metaiodobenzylguanidine (¹²³I-MIBG) imaging in patients with HF and related comorbidities.

METHODS

A comprehensive literature search was conducted on PubMed and Web of Science databases. Articles describing the impact of ¹²³I-MIBG imaging on HF and related comorbidities were considered eligible for the review.

RESULTS

We collected several data reporting that ¹²³I-MIBG imaging is a safe and non-invasive tool to evaluate dysfunction of cardiac sympathetic neuronal function and to assess risk stratification in HF patients. HF is frequently associated with comorbidities that may affect cardiac adrenergic innervation. Furthermore, HF is frequently associated with comorbidities and chronic conditions, such as diabetes, obesity, kidney disease and others, that may affect cardiac adrenergic innervation.

CONCLUSION

Comorbidities and chronic conditions lead to more severe impairment of sympathetic nervous system in patients with HF, with a negative impact on disease progression and outcome. Cardiac imaging with ¹²³I-MIBG can be a useful tool to reduce morbidity and prevent adverse events in HF patients.

Heart failure with preserved ejection fraction: Squaring the circle between comorbidities and cardiovascular abnormalities

Heart Failure with preserved Ejection Fraction (HFpEF) is nowadays considered a major healthcare issue. According to forecasts two third of all Heart Failure patients will belong to this phenotype by year 2050, overwhelming those affected by Heart Failure with reduced Ejection Fraction (HFrEF). Both epidemiological and mechanistic studies support the concept that HFpEF represents true HF although aggravated by a collection of comorbidities. There is urgent need of improving its phenotyping due to the high degree of disease heterogeneity within HFpEF that lead to the failure of randomized clinical trials in demonstrating a remarkable impact of drugs in improving its morbidity and mortality.