Optimizing the quality, quantity, and timing of nutrition holds immense potential to improve health and prevent disease. The results of a recent randomized controlled trial¹ have been widely misrepresented with the incorrect interpretation that optimizing the timing of food intake imparts no health benefits.

Metabolic syndrome (MetS) occurs in ~30% of adults and is associated with increased risk of cardiovascular disease and diabetes mellitus. MetS reflects the clustering of individual cardiometabolic risk factors including central obesity, elevated fasting plasma glucose, dyslipidemia, and elevated blood pressure. Erratic eating patterns such as eating over a prolonged period per day and irregular meal timing are common in patients with MetS. Misalignment between daily rhythms of food intake and circadian timing system can contribute to circadian rhythm disruption which results in abnormal metabolic regulation and adversely impacts cardiometabolic health. Novel approaches which aim at restoring robust circadian rhythms through modification of timing and duration of daily eating represent a promising strategy for patients with MetS. Restricting eating period during a day (time-restricted eating, TRE) can aid in mitigating circadian disruption and improving cardiometabolic outcomes. Previous pilot TRE study of patients with MetS showed the feasibility of TRE and improvements in body weight and fat, abdominal obesity, atherogenic lipids, and blood pressure, which were observed despite no overt attempt to change diet quantity and quality or physical activity. The present article aims at giving an overview of TRE human studies of individuals with MetS or its components, summarizing current clinical evidence for improving cardiometabolic health through TRE intervention in these populations, and presenting future perspectives for an implementation of TRE to treat and prevent MetS. Previous TRE trials laid the groundwork and indicate a need for further clinical research including large-scale controlled trials to determine TRE efficacy for reducing long-term cardiometabolic risk, providing tools for sustained lifestyle changes and, ultimately, improving overall health in individuals with MetS.

Postural orthostatic tachycardia syndrome (POTS) is a complex multisystem disorder characterized by orthostatic intolerance and tachycardia and may be triggered by viral infection. Recent reports indicate that 2%-14% of coronavirus disease 2019 (COVID-19) survivors develop POTS and 9%-61% experience POTS-like symptoms, such as tachycardia, orthostatic intolerance, fatigue, and cognitive impairment within 6-8 months of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Pathophysiological mechanisms of post-COVID-19 POTS are not well understood. Current hypotheses include autoimmunity related to SARS-CoV-2 infection, autonomic dysfunction, direct toxic injury by SARS-CoV-2 to the autonomic nervous system, and invasion of the central nervous system by SARS-CoV-2. Practitioners should actively assess POTS in patients with post-acute COVID-19 syndrome symptoms. Given that the symptoms of post-COVID-19 POTS are predominantly chronic orthostatic tachycardia, lifestyle modifications in combination with the use of heart rate-lowering medications along with other pharmacotherapies should be considered. For example, ivabradine or β-blockers in combination with compression stockings and increasing salt and fluid intake has shown potential. Treatment teams should be multidisciplinary, including physicians of various specialties, nurses, psychologists, and physiotherapists. Additionally, more resources to adequately care for this patient population are urgently needed given the increased demand for autonomic specialists and clinics since the start of the COVID-19 pandemic. Considering our limited understanding of post-COVID-19 POTS, further research on topics such as its natural history, pathophysiological mechanisms, and ideal treatment is warranted. This review evaluates the current literature available on the associations between COVID-19 and POTS, possible mechanisms, patient assessment, treatments, and future directions to improving our understanding of post-COVID-19 POTS.

Introduction

Cardiac rehabilitation (CR) significantly reduces secondary cardiovascular events and mortality and is a class 1A recommendation by the American Heart Association (AHA) and American College of Cardiology (ACC). However, it remains an underutilized intervention and many eligible patients fail to enroll or complete CR programs. The aim of this review is to identify barriers to CR attendance and discuss strategies to overcome them.

Areas covered

Specific barriers to CR attendance and participation will be reviewed. This will be followed by a discussion of solutions/strategies to help overcome these barriers with a particular focus on home-based CR (HBCR).

Expert opinion

HBCR alone or in combination with center-based CR (CBCR) can help overcome many barriers to traditional CBCR participation, such as schedule flexibility, time commitment, travel distance, cost, and patient preference. Using remote coaching with indirect exercise supervision, HBCR has been shown to have comparable benefits to CBCR. At this time, however, funding remains the main barrier to universal incorporation of HBCR into health systems, necessitating the need for additional cost benefit analysis and outcome studies. Ultimately, the choice for HBCR should be based on patient preference and availability of resources.

Purpose of review

The COVID-19 pandemic has forced many center-based cardiac rehabilitation (CBCR) programs to close or limit their usual offerings. In order for patients to continue to benefit from CR, programs need to rapidly adapt to the current environment. This review highlights ways CR has evolved, and reviews the history of CR and recent advancements in telemedicine including remote patient monitoring, and mobile health that can be applied to CR.

Recent findings

Despite that initial studies indicate that home-based CR (HBCR) is safe and effective, HBCR has faced several challenges that have prevented it from becoming more widely implemented. Many previous concerns can now be addressed through the use of new innovations in home-based healthcare delivery. Since its inception, CR has become increasingly recognized as an important tool to improve patient mortality and quality of life in a broad range of cardiac diseases. While there has been little need to modify the delivery of CR since the 1950s, COVID-19 now serves as the necessary impetus to make HBCR an equal alternative to CBCR.

Acute ST-segment elevation myocardial infarction (STEMI) activates inflammation that can contribute to left ventricular systolic dysfunction (LVSD) and heart failure (HF). The objective of this study was to examine whether high-sensitivity C-reactive protein (CRP) concentration is predictive of long-term post-infarct LVSD and HF. In 204 patients with a first STEMI, CRP was measured at hospital admission, 24 h (CRP24), discharge (CRPDC), and 1 month after discharge (CRP1M). LVSD at 6 months after discharge (LVSD6M) and hospitalization for HF in long-term multi-year follow-up were prospectively evaluated. LVSD6M occurred in 17.6% of patients. HF hospitalization within a median follow-up of 5.6 years occurred in 45.7% of patients with LVSD6M vs. 4.9% without LVSD6M (p < 0.0001). Compared to patients without LVSD6M, the patients with LVSD6M had higher CRP24 and CRPDC and persistent CRP1M ≥ 2 mg/L. CRP levels were also higher in patients in whom LVSD persisted at 6 months (51% of all patients who had LVSD at discharge upon index STEMI) vs. patients in whom LVSD resolved. In multivariable analysis, CRP24 ≥ 19.67 mg/L improved the prediction of LVSD6M with an increased odds ratio of 1.47 (p < 0.01). Patients with LVSD6M who developed HF had the highest CRP during index STEMI. Elevated CRP concentration during STEMI can serve as a synergistic marker for risk of long-term LVSD and HF.

A 32-year-old woman with a history of symptomatic supraventricular tachycardia, inappropriate sinus tachycardia, and hyperadrenergic POTS was treated with ivabradine and metoprolol. She then presented with bradycardia and Mobitz II second-degree AV block on event monitoring six weeks after COVID-19 infection. Her post-viral workup revealed normalization of catecholamine levels and significant symptomatic improvement in heart rate. To the authors' knowledge, this is the first reported case of improvement in POTS after COVID-19 infection. As our understanding of COVID-19 continues to improve, it will be vital to better understand the impact of COVID-19 dysautonomia on cardiac patients.

Structured lifestyle interventions through cardiac rehabilitation (CR) are critical to improving the outcome of patients with cardiovascular disease (CVD) and cardiometabolic risk factors. CR programs' variability in real-world practice may impact CR effects. This study evaluates intensive CR (ICR) and standard CR (SCR) programs for improving cardiometabolic, psychosocial, and clinical outcomes in high-risk CVD patients undergoing guideline-based therapies. Both programs provided lifestyle counseling and the same supervised exercise component. ICR additionally included a specialized plant-based diet, stress management, and social support. Changes in body weight (BW), low-density lipoprotein cholesterol (LDL-C), and exercise capacity (EC) were primary outcomes. A total of 314 patients (101 ICR and 213 SCR, aged 66 ± 13 years, 75% overweight/obese, 90% coronary artery disease, 29% heart failure, 54% non-optimal LDL-C, 43% depressive symptoms) were included. Adherence to ICR was 96% vs. 68% for SCR. Only ICR resulted in a decrease in BW (3.4%), LDL-C (11.3%), other atherogenic lipids, glycated hemoglobin, and systolic blood pressure. Both ICR and SCR increased EC (52.2% and 48.7%, respectively) and improved adiposity indices, diastolic blood pressure, cholesterol intake, depression, and quality of life, but more for ICR. Within 12.6 ± 4.8 months post-CR, major adverse cardiac events were less likely in the ICR than SCR group (11% vs. 17%), especially heart failure hospitalizations (2% vs. 8%). A comprehensive ICR enhanced by a plant-based diet and psychosocial management is feasible and effective for improving the outcomes in high-risk CVD patients in real-world practice.

Background

We sought to determine whether management of LDL-C following invasive angiography and assessment by fractional flow reserve (FFR) differs between those with obstructive vs non-obstructive CAD.

Methods

Retrospective study of 721 patients undergoing coronary angiography involving assessment by FFR between 2013 and 2020 at a single academic center. Groups with obstructive vs non-obstructive CAD by index angiographic and FFR findings were compared over 1 year of follow-up.

Results

Based on index angiographic and FFR findings, 421 (58%) patients had obstructive CAD vs 300 (42%) with non-obstructive CAD, mean (±SD) age 66±11 years, 217 (30%) women, and 594 (82%) white. There was no difference in baseline LDL-C. At 3-months follow-up, LDL-C was lower than baseline in both groups, with no between group difference. In contrast, at 6-months, median (Q1, Q3) LDL-C was significantly higher in non-obstructive vs obstructive CAD (LDL-C 73 (60, 93) vs 63 (48, 77) mg/dL, respectively (p = 0.003), (p = 0.001 in multivariable linear regression)). At 12-months, LDL-C remained higher in non-obstructive vs obstructive CAD (LDL-C 73 (49, 86) vs 64 (48, 79) mg/dL, respectively, although not statistically significant (p = 0.104)). The rate of high-intensity statin use was lower among those with non-obstructive CAD vs obstructive CAD at all time points (p < 0.05).

Conclusions

After coronary angiography involving FFR, there is intensification of LDL-C lowering at 3-months follow-up in both obstructive and non-obstructive CAD. However, by 6-months follow-up LDL-C is significantly higher among those with non-obstructive CAD vs obstructive CAD. Following coronary angiography involving FFR, patients with non-obstructive CAD may benefit from greater attention to LDL-C lowering to reduce residual ASCVD risk.

Aims

This analysis assessed the efficacy and safety of alirocumab, a proprotein convertase subtilisin/kexin type 9 inhibitor, in patients with or without metabolic syndrome (MetS) using pooled data from 10 phase 3 ODYSSEY trials.

Materials and methods

Data from 4983 randomized patients (1940 with MetS; 1642 with diabetes excluded) were assessed in subgroups by MetS status. Efficacy data were analysed in 4 pools per study design: 2 placebo-controlled pools (1 using alirocumab 150 mg every 2 weeks [Q2W], 1 using 75/150 mg Q2W) with background statin, and 2 ezetimibe-controlled pools (both alirocumab 75/150 mg Q2W), 1 with and 1 without background statin. Alirocumab 75/150 mg indicates possible dose increase from 75 to 150 mg at Week 12 based on Week 8 LDL-C.

Results

LDL-C percentage reduction from baseline at Week 24 with alirocumab was 63.9% (MetS) and 56.8% (non-MetS) in the pool of alirocumab 150 mg Q2W, and 42.2% to 52.2% (MetS) and 45.0% to 52.6% (non-MetS) in 3 pools using 75/150 mg Q2W. Levels of other lipid and lipoprotein parameters were also improved with alirocumab treatment, including apolipoprotein B, non-high-density lipoprotein cholesterol (non-HDL-C), lipoprotein(a) and HDL-C. Overall, the percentage change at Week 24 in LDL-C and other lipids and lipoproteins did not vary by MetS status. Adverse event rates were generally similar between treatment groups, regardless of MetS status; injection-site reactions occurred more frequently in alirocumab vs control groups.

Conclusions

Across study pools, alirocumab-associated reductions in LDL-C, apolipoprotein B, and non-HDL-C were significant vs control, and did not vary by MetS status.