Influence of cardiometabolic comorbidities on myocardial function, infarction, and cardioprotection: Role of cardiac redox signaling

The morbidity and mortality from cardiovascular diseases (CVD) remain high. Metabolic diseases such as obesity, hyperlipidemia, diabetes mellitus (DM), non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) as well as hypertension are the most common comorbidities in patients with CVD. These comorbidities result in increased myocardial oxidative stress, mainly from increased activity of nicotinamide adenine dinucleotide phosphate oxidases, uncoupled endothelial nitric oxide synthase, mitochondria as well as downregulation of antioxidant defense systems. Oxidative and nitrosative stress play an important role in ischemia/reperfusion injury and may account for increased susceptibility of the myocardium to infarction and myocardial dysfunction in the presence of the comorbidities. Thus, while early reperfusion represents the most favorable therapeutic strategy to prevent ischemia/reperfusion injury, redox therapeutic strategies may provide additive benefits, especially in patients with heart failure. While oxidative and nitrosative stress are harmful, controlled release of reactive oxygen species is however important for cardioprotective signaling. In this review we summarize the current data on the effect of hypertension and major cardiometabolic comorbidities such as obesity, hyperlipidemia, DM, NAFLD/NASH on cardiac redox homeostasis as well as on ischemia/reperfusion injury and cardioprotection. We also review and discuss the therapeutic interventions that may restore the redox imbalance in the diseased myocardium in the presence of these comorbidities.

Dysglycemia and increased left ventricle mass in normotensive patients admitted with a first myocardial infarction: prognostic implications of dysglycemia during 14 years of follow-up

Background

Left ventricle mass (LVM) can be influenced by various conditions including hypertension and/or inherent cardiomyopathies. Dysglycemia is also thought to exert an anabolic effect on heart tissue by hyperinsulinemia and thereby promoting increased LVM. The primary aim of this study was to assess the influence of dysglycemia on LVM evaluated by an oral glucose tolerance test (OGTT) in patients admitted with a first myocardial infarction (MI) without hypertension. The secondary aim was to assess the impact of dysglycemia on major adverse cardiovascular events (MACE) and all-cause mortality during long-term follow-up.

Methods

Patients admitted with a first MI without known history of hypertension were included. All patients without previously known type 2 diabetes mellitus (T2DM) had a standardized 2-hour OGTT performed and were categorized as: normal glucose tolerance (NGT), impaired fasting glucose (IFG)/impaired glucose tolerance (IGT) and newly detected T2DM (new T2DM). LVM was measured by echocardiography using Devereaux formula and indexed by body surface area. Multivariate linear regression analysis was used to assess the impact of confounders (dysglycemia by OGTT, known T2DM, age, sex and type of MI) on LVM. Cox proportional hazard model was used to assess the impact of dysglycemia on all-cause mortality and a composite endpoint of MACE (all-cause mortality, MI, revascularisation due to stable angina, coronary artery bypass graft, ischemic stroke or hemorrhagic stroke).

Results

Two-hundred-and-five patients were included and followed up to 14 years. In multivariate regression analysis, LVM was only significantly increased in patients categorized as new T2DM (β = 25.3; 95% CI [7.5–43.0]) and known T2DM (β = 37.3; 95% CI [10.0-64.5]) compared to patients with NGT. Patients with new T2DM showed higher rates of MACE and all-cause mortality compared to patients with IFG/IGT and NGT; however no significantly increased hazard ratio was detected.

Conclusions

Dysglycemia is associated with increasing LVM in normotensive patients with a first acute myocardial infarction and the strongest association was observed in patients with new T2DM and patients with known T2DM. Dysglycemia in normotensive patients with a first MI is not an independent predictor of neither MACE nor all-cause mortality during long-term follow-up compared to normotensive patients without dysglycemia.

Electronic supplementary material

The online version of this article (10.1186/s12872-019-1084-5) contains supplementary material, which is available to authorized users.

Prognostic Significance of Presenting Blood Pressure in Patients With ST-Elevation Myocardial Infarction Undergoing Percutaneous Coronary Intervention

BACKGROUND

We evaluated the impact of normal vs. high presenting blood pressure (BP) on clinical outcomes and cardiac function in patients with ST-elevation myocardial infarction (MI).

METHODS

In 11,292 patients, in-hospital mortality and major adverse clinical events (MACE; all-cause death, nonfatal MI, or any revascularization) during follow-up were compared between patients with normal (≥ 100 mm Hg and ≤ 139 mm Hg) and high (≥ 140 mm Hg) systolic BP at presentation.

RESULTS

Compared to patients with high BP, patients with normal BP had significantly higher in-hospital mortality (1.5% vs. 3.7%; P < 0.001), especially in those with prior hypertension, and higher rates of all-cause death (3.3% vs. 5.3%; P < 0.001) and MACE (9.8% vs. 11.8%; P = 0.04) during follow-up (median: 330 days). After multivariate adjustment, normal BP was associated with higher risk of in-hospital mortality (adjusted hazard ratio (HR) = 2.268; 95% confidence interval (CI) = 1.144-4.498; P = 0.019), but not all-cause death (adjusted HR = 0.956; 95% CI = 0.602-1.517) or MACE (adjusted HR = 0.935; 95% CI = 0.755-1.158). Left ventricular ejection fraction at baseline and follow-up was significantly lower in patients with normal BP (52% vs. 51%; P < 0.001 and 55% vs. 54%; P = 0.018, respectively).

CONCLUSIONS

Our findings indicate that patients with normal presenting BP, especially those with prior hypertension, exhibit higher in-hospital mortality and poorer cardiac function compared to patients with high BP. Although outcomes during follow-up did not differ, cardiac function was persistently poorer in patients who presented with normal BP.

Use of contrast echocardiography in intensive care and at the emergency room

Bedside echocardiography in emergency room (ER) or in intensive care unit (ICU) is an important tool for managing critically ill patients, to obtain a timely accurate diagnosis and to immediately stratify the risk to the patient’s life. It may also render invasive monitoring unnecessary. In these patients, contrast echocardiography may improve quality of imaging and also may provide additional information, especially regarding myocardial perfusion in those with suspected coronary artery disease. This article focuses on the principle of contrast echocardiography and the clinical information that can be obtained according to the most frequent presentations in ER and ICU.