Cardiocytic apoptosis and capillary endothelial swelling as morphological evidence of myocardial ischemia in ventricular biopsies from patients with angina and normal coronary arteriograms

Serum prolidase activity in patients with cardiac syndrome X

OBJECTIVE:

Although the underlying mechanism is not yet fully understood, Cardiac Syndrome X (CSX) is defined as microvascular dysfunction. Prolidase plays a role in collagen synthesis. Increased serum prolidase activity (SPA) has been shown to correlate with collagen turnover. Augmented collagen turn-over may be associated with vascular fibrosis and microvascular dysfunction. In this study, we assessed whether there was a correlation between CXS and prolidase activity.

METHODS:

This case-control study included 45 consecutive CSX patients (mean age 50.7±6.5 years, 27 women) and 40 healthy controls (mean age 51.2±6.5 years, 25 women). Prolidase activity was determined with the Human Xaa-Pro Dipeptidase/Prolidase enzyme-linked immunosorbent assay kit (Cusabio Biotech Co. Ltd, China).

RESULTS:

Mean prolidase activity was 898.8±639.1 mU/mL in the CSX group and 434.1±289.8 mU/mL in the control group (p<0.001). In ROC analysis, it was found that the SPA value above 350 mU/mL sympathizes with the diagnosis of CSX.

CONCLUSION:

Increased SPA in CXS patients may play an essential role in the pathophysiology of CSX, leading to augmented oxidative stress and vascular fibrosis, endothelial dysfunction, and increased microvascular resistance.

Adult ALCAPA: from histological picture to clinical features

BACKGROUND

Anomalous left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital coronary anomaly that results in high mortality if left untreated. Our aim was to extend our knowledge of the histological, angiographic, and clinical characteristics of ALCAPA in order to deepen our understanding of this rare entity.

CASE PRESENTATION

We were involved in the assessment, treatment, and pathological evaluation of two adult ALCAPA patients who were rescued from ventricular fibrillation and then surgically treated to establish a dual coronary artery system. Histological studies indicated various chronic ischemic changes in the myocardium, patchy fibrosis, and severely thickened arteriolar walls in both ventricles. The first patient is alive and well 11.5 years after surgical correction without any implantable cardioverter defibrillator (ICD) activations. The second patient required re-do surgery 9 months after the initial operation but subsequently died. Histologically, chronic ischemic alteration of the myocardium and thickened arteriolar walls persisted even after surgical correction, and coronary angiography (CAG) showed an extremely slow flow phenomenon even after surgical correction in both patients. The average postoperative opacification rate in the first case was 7.36 + 1.12 (n = 2) in the RCA, 3.81 + 0.51 (n = 3) in the left anterior descending (LAD) artery, and 4.08 + 0.27 (n = 4) in the left circumflex (LCx) artery. The slow flow phenomenon may represent persistent high arteriolar resistance in both ventricles.

CONCLUSIONS

Seldom reported or new findings in adult ALCAPA were identified in two cases. More frequent diagnosis of adult ALCAPA can be expected because of the widespread availability of resuscitation and more advanced diagnostic modalities. Accumulation of pathological and clinical findings and confirmation of the long-term follow-up results after treatment may contribute to expanding our knowledge of this rare entity and establishing optimal treatment.

Evaluation of serum sST2 and sCD40L values in patients with microvascular angina

OBJECTIVES

Coronary microvascular dysfunction plays a major role in the pathogenesis of microvascular angina (MVA). Along with endothelial dysfunction, microvascular atherosclerosis and inflammation seem to contribute to the development of coronary microvascular dysfunction. Serum soluble ST2 (sST2) and serum soluble CD40 ligand (sCD40L) are two biomarkers associated with inflammation and atherosclerosis. The aim of this study was to investigate the role of these biomarkers in the pathogenesis of MVA and determine their possible association with coronary microvascular dysfunction.

METHODS

A total of 152 patients were included in the study. Ninety-one patients with MVA {median age 56 years (40-79), of which 55 are women} and sixty-one controls {median age 52 (38-76), of which 29 are women} were included in the study. Serum concentration of sST2 and sCD40L were measured with a commercially available ELISA kit.

RESULTS

Serum sST2 (median 13.6 ng/ml; interquartile range (IQR), 3.5-63.8 ng/ml vs median 10.6 ng/ml; IQR, 2.9-34.2 ng/ml, p < 0.0005) and sCD40L (median 5.3 ng/ml; IQR, 0.5-20.6 ng/ml vs median 2.2 ng/ml; IQR, 0.7-10.8 ng/ml, p < 0.0005) were significantly higher in patients with MVA compared to controls. Analysis of the associations between these biomarkers and potential contributors of MVA revealed that serum sST2 showed a positive correlation with LDL-cholesterol (r = 0.19, p = 0.016) and serum sCD40L concentrations correlated positively with hs-CRP (r = 0.22, p = 0.005). In logistic regression analysis, sCD40L and hs-CRP but not sST2 were found to be significantly associated with MVA.

CONCLUSION

Higher serum concentrations of sST2 and sCD40L in MVA patients may be associated with inflammatory activation and coronary microvascular dysfunction. Larger studies are required for understanding their role in the pathogenesis of inflammatory and possibly fibrotic process in MVA patients.

Stable coronary syndromes: pathophysiology, diagnostic advances and therapeutic need

The diagnostic management of patients with angina pectoris typically centres on the detection of obstructive epicardial CAD, which aligns with evidence-based treatment options that include medical therapy and myocardial revascularisation. This clinical paradigm fails to account for the considerable proportion (approximately one-third) of patients with angina in whom obstructive CAD is excluded. This common scenario presents a diagnostic conundrum whereby angina occurs but there is no obstructive CAD (ischaemia and no obstructive coronary artery disease—INOCA). We review new insights into the pathophysiology of angina whereby myocardial ischaemia results from a deficient supply of oxygenated blood to the myocardium, due to various combinations of focal or diffuse epicardial disease (macrovascular), microvascular dysfunction or both. Macrovascular disease may be due to the presence of obstructive CAD secondary to atherosclerosis, or may be dynamic due to a functional disorder (eg, coronary artery spasm, myocardial bridging). Pathophysiology of coronary microvascular disease may involve anatomical abnormalities resulting in increased coronary resistance, or functional abnormalities resulting in abnormal vasomotor tone. We consider novel clinical diagnostic techniques enabling new insights into the causes of angina and appraise the need for improved therapeutic options for patients with INOCA. We conclude that the taxonomy of stable CAD could improve to better reflect the heterogeneous pathophysiology of the coronary circulation. We propose the term ‘stable coronary syndromes’ (SCS), which aligns with the well-established terminology for ‘acute coronary syndromes’. SCS subtends a clinically relevant classification that more fully encompasses the different diseases of the epicardial and microvascular coronary circulation.

Different definition of microvascular angina

We sometimes encounter patients with microvascular angina (MVA), a disease characterized by anginal pain without abnormal coronary arteriographic findings or coronary spasm. More than 40 years have passed since MVA was first confirmed. The terms 'syndrome X', 'cardiac syndrome X' and 'microvascular dysfunction' have also been used to describe conditions similar to MVA, but all with slightly different definitions. The cause of MVA seems almost certain to be organic and functional abnormalities of the small arteries of the heart. Patients with MVA are likely to suffer from endothelial dysfunction and other microvascular abnormalities of both the coronary and peripheral arteries. The major treatment of MVA has been medication, most often calcium channel blockers. The prognosis of MVA is generally excellent, although symptoms remain in many studies. Some MVA patients with accompanying hypertensive heart disease have gone on to develop progressive left ventricular dysfunction, with poor prognosis. The different definitions applied to the terms used to describe this condition, what we refer to here as MVA, can confound issues involved in diagnosis, prognosis and proper treatment. Therefore, it is extremely important to distinguish primary MVA without underlying heart disease from secondary MVA to explore the disease mechanism and examine the clinical characteristics. It is more than 40 years since Likoff first confirmed this disease; therefore, all researchers know that strict diagnostic criteria for MVA should be immediately established.

Serum concentrations of galectin-3 in patients with cardiac syndrome X

OBJECTIVE

Microvascular dysfunction has been reported in cardiac syndrome X (CSX), even though the underlying mechanisms still remain uncertain. Galectin-3 has been recently recognized as a biomarker of cardiovascular fibrosis and inflammation. We sought to investigate the role of galectin-3 in the CSX.

METHODS

We studied 115 consecutive CSX patients (mean age 55.43 ± 8.71 years, 36 men) and 74 healthy controls (mean age 54.53 ± 10.07 years, 31 men). Serum concentrations of galectin-3 and high-sensitive C-reactive protein (hs-CRP) were measured on the blood samples.

RESULTS

Galectin-3 concentrations were significantly higher in patients with CSX compared to controls (0.90 ng/ml; IQR, 0.40-1.70 ng/ml vs 0.40 ng/ml; IQR, 0.36-0.44 ng/ml, p < 0.0001). Although, the prevalence of diabetes mellitus, hypertension and family history of coronary artery disease (CAD) were significantly higher among patients with CSX, following adjustment for diabetes mellitus, hypertension, and family history of CAD, serum galectin-3 concentrations were still found significantly increased in patients with CSX. Galectin-3 concentrations correlated positively with hs-CRP (r = 0.16, p = 0.03). In addition, concentrations of galectin-3, hs-CRP, fasting glucose, uric acid and family history of CAD were determined as independent predictors of the CSX.

CONCLUSION

It was found that galectin-3 serum concentrations are higher in patients with CSX compared to healthy controls. Further studies on larger population are needed to confirm the relation between the fibrosis and the CSX, as well as to explore the potential role of galectin-3 in the CSX.

N-terminal pro-brain natriuretic protein levels in takotsubo cardiomyopathy

Takotsubo cardiomyopathy (TTC) is characterized by reversible left ventricular (LV) systolic dysfunction independent of fixed coronary disease or coronary spastic pathogenesis. A number of investigators have documented marked elevation of natriuretic peptide levels at presentation in such patients. We sought to determine the pattern, extent, and determinants of the release of N-terminal pro-B type natriuretic peptide/B type natriuretic peptide (NT-proBNP/BNP) in patients with TTC. We evaluated NT-proBNP/BNP release acutely and during the first 3 months in 56 patients with TTC (96% women, mean age 69 ± 11 years). The peak plasma NT-proBNP levels were compared to the pulmonary capillary wedge pressure and measures of regional and global LV systolic dysfunction (systolic wall stress, wall motion score index, and LV ejection fraction) as potential determinants of NT-proBNP/BNP release. In patients with TTC, the plasma concentrations of NT-proBNP (median 4,382 pg/ml, interquartile range 2,440 to 9,019) and BNP (median 617 pg/ml, interquartile range 426 to 1,026) were substantially elevated and increased significantly during the first 24 hours after the onset of symptoms (p = 0.001), with slow and incomplete resolution during the 3 months thereafter. The peak NT-proBNP levels exhibited no significant correlation with either pulmonary capillary wedge pressure or systolic wall stress. However, the peak NT-proBNP level correlated significantly with the simultaneous plasma normetanephrine concentrations (r = 0.53, p = 0.001) and the extent of impairment of LV systolic function, as measured by the wall motion score index (r = 0.37, p = 0.008) and LV ejection fraction (r = -0.39, p = 0.008). In conclusion, TTC is associated with marked and persistent elevation of NT-proBNP/BNP levels, which correlated with both the extent of catecholamine increase and the severity of LV systolic dysfunction.

Chinese medicinal formula Guan-Xin-Er-Hao protects the heart against oxidative stress induced by acute ischemic myocardial injury in rats

Guan-Xin-Er-Hao (GXEH) is a Chinese medicine formula for treating ischemic heart diseases (IHD) and has a favorable effect. Our aim was to examine whether or not acute oral GXEH could protect the heart against myocardial infarction and apoptosis in acute myocardial ischemic rats. If so, we would explain the antioxidative mechanism involved. The left anterior descending coronary artery was occluded to induce myocardial ischemia in hearts of Sprague-Dawley rats. At the end of the 3h ischemic period (or 24h for infarct size), we measured the myocardial infarct size, myocardial apoptosis and the activities of antioxidative enzymes. GXEH reduced infarct size, myocardial apoptosis and the serum level of malondialdehyde (MDA), increased the activities of total antioxidant capacity (T-AOC), superoxide dismutase (SOD) and GSH-peroxidase (GPX) activities and the serum level of glutathione (GSH). GXEH exerts significant cardioprotective effects against acute ischemic myocardial injury in rats, likely through its antioxidation and antilipid peroxidative properties, and thus may be used as a promising agent for both prophylaxis and treatment of IHD.

An approach to endomyocardial biopsy interpretation

The endomyocardial biopsy (EMB) remains the gold standard mode of investigation for diagnosing many primary and secondary cardiac conditions. Through a percutaneous and transvenous route, tissue fragments are generally procured from the right ventricular septum, with very few complications. Widespread use of EMB followed the development of heart transplantation as a means to follow allograft rejection. It has since been useful in helping to diagnose conditions affecting the heart, including cardiomyopathies, myocarditis, infiltrative lesions, arrhythmias, and drug toxicities. The procedure has also been used as a research tool to investigate the natural history of disease and the cardiotoxicity of new medications. This review presents an approach to the evaluation of the EMB, which is particularly directed towards those who may be asked to interpret such biopsies, but are not dedicated cardiovascular pathologists. Through a systematic evaluation of the endocardium, myocardium, interstitium, and intramural vessels, in the context of a complete clinical history, enough information can be deduced to diagnose or exclude specific conditions of clinical value.