Mechanisms of Myocardial Infarction in Patients With Nonobstructive Coronary Artery Disease: Results From the Optical Coherence Tomography Study.

OBJECTIVES: This study sought to assess the presence and morphological features of coronary plaques on optical coherence tomography (OCT) as the causes of myocardial infarction with nonobstructive coronary arteries (MINOCA). BACKGROUND: Although coronary atherosclerosis has been postulated as a potential mechanism of MINOCA, the interaction between disrupted coronary plaques and myocardial injury remains unknown. METHODS: In a prospective study, consecutive patients with MI but without significant coronary stenosis (≥50%) at angiography underwent OCT and cardiac magnetic resonance (CMR) with late gadolinium-enhancement (LGE). The infarct-related artery (IRA) was identified by localization of ischemic-type LGE. RESULTS: Thirty-eight MINOCA patients (mean age 62 ± 13 years, 55% female, 39% with ST-segment elevation) were enrolled. Maximal diameter stenosis was 35% by angiography, and 5 patients (13%) had normal angiogram results. Plaque disruption and coronary thrombus were observed in 9 patients (24%) and 7 patients (18%), respectively. Sixteen of 31 patients (52%) undergoing CMR showed LGE. Ischemic-type LGE was present in 7 patients (23%) and was more common in patients with than without plaque disruption (50% vs. 13%, respectively; p = 0.053) and coronary thrombus (67% vs. 12%, respectively; p = 0.014). In the per-lesion analysis, the IRA showed significantly more plaque disruption (40% vs. 6%; p = 0.02), thrombus (50% vs. 4%; p = 0.014), and thin-cap fibroatheroma (70% vs. 30%; p = 0.03) than the non-IRA. CONCLUSIONS: Plaque disruption and thrombus are not uncommon in MI without obstructive coronary stenoses at angiography and may be associated with the presence and location of ischemic-type myocardial injury on CMR. OCT may be valuable in identifying atherosclerotic etiology in individuals with MINOCA. (Optical Coherence Tomography in Patients With Acute Myocardial Infarction and Nonobstructive Coronary Artery Disease [SOFT-MI]; NCT02783963).

Patterns of changes in functional and neurocognitive status in elderly patients after transcatheter vs. surgical aortic valve replacements.

BACKGROUND: Replacement of severely stenotic aortic valve may influence cognitive and physical functioning. The aim of this study was to compare cognitive and functional status after surgical (SAVR) vs. transcatheter aortic valve replacements (TAVR) in the elderly with severe aortic stenosis (AS). METHODS: It was a prospective observational study with over 6 months of follow-up. Eighty ≥70-year-old patients with AS underwent TAVR (N.=40) or SAVR (N.=40). Mini Mental State Exam (MMSE), activities daily living (ADL) score and instrumental activities daily living (IADL) score were used to assess the cognitive status, fundamental functioning and complex independent living skills, respectively. The tests were conducted at baseline and 6 months after the procedure. Additionally, MMSE was carried out at discharge. RESULTS: Baseline MMSE score was lower in the TAVR vs. SAVR group (P=0.001). In the SAVR group, there was a transient in-hospital decline in mean MMSE score (P=0.020), absent in the TAVR group. Baseline ADL and IADL scores were lower in TAVR patients. Both groups experienced mild improvement. The average increase among those with improved IADL score was larger after TAVR (2.37 vs. 1.37 after SAVR; P=0.029). A systolic blood pressure (SBP) decrease <60 mmHg as well as larger periprocedural shift in SBP (expressed by a difference between maximum and minimum SBP) during TAVR were associated with the decline in the ADL (P=0.001) and IADL scores (P=0.043). CONCLUSIONS: Cognitive patterns differed between the TAVR and SAVR patients. A transient MMSE decline did not alter the 6-month status. TAVR might improve functionality. Periprocedural SBP decrease and larger changes in SBP are risk factors for functionality deterioration after TAVR.

Serum beta-2 microglobulin levels for predicting acute kidney injury complicating aortic valve replacement.

OBJECTIVES: Acute kidney injury complicating both transcatheter and surgical aortic valve replacement is associated with high rates of morbidity and mortality. The aim of this study was to investigate the role of serum beta 2 (ß2) microglobulin, cystatin C and neutrophil gelatinase-associated lipocalin levels in detecting periprocedural acute kidney injury. METHODS: Eighty consecutive patients who were 70 years of age or older and who were having surgical (n = 40) or transcatheter (n = 40) aortic valve replacement were recruited in a prospective study. The biomarkers were tested before the procedure, 6 times afterwards, at discharge and at a 6-month follow-up visit. RESULTS: The baseline ß2-microglobulin level was the strongest predictor of acute kidney injury as a complication of transcatheter aortic valve replacement [odds ratio (OR) 5.277, P = 0.009]. Its level 24 h after the procedure reached the largest area under the curve (AUC) of 0.880 (P < 0.001) for detecting acute kidney injury. In multivariate logistic regression analysis, the levels of ß2-microglobulin and cystatin C 24 h after the procedure were significantly associated with acute kidney injury after transcatheter valve replacement (OR 38.15, P = 0.044; OR 1782, P = 0.019, respectively). In the surgical aortic valve replacement group, the highest AUCs belonged to ß2-microglobulin and cystatin C at 24 h (AUC = 0.808, P = 0.003 and AUC = 0.854, P = 0.001, respectively). Their higher values were also associated with acute kidney injury (OR 17.2, P = 0.018; OR 965.6, P = 0.02, respectively). A persistent increase in the postoperative levels of ß2-microglobulin following acute kidney injury was associated with the progression of chronic kidney disease for 6 months after both transcatheter (OR 6.56, P = 0.030) and surgical (OR 7.67, P = 0.03) aortic valve replacements. CONCLUSIONS: Serum ß2-microglobulin had the potential to predict acute kidney injury complicating transcatheter valve replacement and to diagnose it as early as 24 h after both the transcatheter and the surgical procedures. Furthermore, the serum level of ß2-microglobulin was indicative of the progression of chronic kidney disease.

PPAR Gamma Expression Levels during Development of Heart Failure in Patients with Coronary Artery Disease after Coronary Artery Bypass-Grafting.

Genetic research has elucidated molecular mechanisms of heart failure (HF). Peroxisome proliferator-activated receptors (PPARs) seem to be important in etiology of HF. The aim of study was to find the correlation between PPARγ expression during development of HF in patients and coronary artery disease (CAD) after coronary artery bypass-grafting (CABG). Methods and Results. We followed up 157 patients (mean age 63) with CAD without clinical, laboratory, or echo parameters of HF who underwent CABG. Clinical and laboratory status were assessed before CABG and at 1, 12, and 24 months. During CABG slices of aorta (Ao) and LV were collected for genetic research. HF was defined as LVEF <40% or NT-proBNP >400 pg/mL or 6MWT <400 m. Patients were divided into 2 groups: with and without HF. PPARγ expression in Ao and LV was not increased in both groups at 2-year follow-up. Sensitivity of PPARγ expression in Ao above 1.1075 in detection of HF was 20.5% (AUC 0.531, 95% CI 0.442-0.619). Positive predictive value (Ppv) was 85.7%. Sensitivity and specificity of PPARγ expression in the LV in detection of HF were 58% and 92.9%, respectively (AUC 0.540, 95% CI 0.452-0.626). Ppv was 73.2%. Conclusion. PPARγ expression in Ao and LV was comparable and should not be used as predictive factor for development of HF in patients with CAD after CABG.