Coronary microcirculation in nonculprit vessel territory in reperfused acute myocardial infarction.

BACKGROUND: There is an ongoing debate on the extension of reperfusion-related microvascular damage (MVD) throughout the remote noninfarcted myocardial regions in patients with ST-elevation myocardial infarction (STEMI) that undergo primary percutaneous intervention (pPCI). The aim of this study was to elucidate the impact of reperfusion on remote microcirculatory territory by analyzing hemodynamic alterations in the nonculprit-vessel in relation to reperfusion. METHODS: A total of 20 patients with STEMI undergoing pPCI were included. Peri-reperfusion temporal changes in hemodynamic parameters were obtained in angiographically normal nonculprit vessels before and 1-h after reopening of the culprit vessel. Intracoronary pressure and flow velocity data were compared using pairwise analyses (before and 1-h after reperfusion). RESULTS: In the non-culprit vessel, compared to the pre-reperfusion state, mean resting average peak velocity (33.4 ± 9.4 to 25.0 ± 4.9 cm/s, P < 0.001) and mean hyperemic average peak velocity (53.5 ± 14.4 to 42.1 ± 10.66 cm/s, P = 0.001) significantly decreased; whereas baseline (3.2 ± 1.0 to 4.0 ± 1.0 mmHg.cm-1.s, P < 0.001) and hyperemic microvascular resistance (HMR) (1.9 ± 0.6 to 2.4 ± 0.7 mmHg.cm-1.s, P < 0.001) and mean zero flow pressure (Pzf) values (32.5 ± 6.9 to 37.6 ± 8.3 mmHg, P = 0.003) significantly increased 1-h after reperfusion. In particular, the magnitude of changes in HMR and Pzf values following reperfusion were more prominent in patients with larger infarct size and with higher extent of MVD in the culprit vessel territory. CONCLUSION: Reperfusion-related microvascular injury extends to involve remote myocardial territory in relation to the magnitude of the adjacent infarction and infarct-zone MVD. (GUARD Clinical TrialsNCT02732080).

Galectin-3 as a Novel Biomarker for Predicting Clinical Outcomes in Hospitalized COVID-19 Patients.

BACKGROUND: Galectin-3 has been shown to play a key pathophysiological role in pulmonary associated inflammatory response and lung fibrosis in COVID-19 and is a mediator for viral adhesion. However, there is limited data about its potential role in severity and prognosis of COVID-19. This study aimed to investigate the predictive role of serum galectin-3 concentrations in the severe clinical outcomes of hospitalized COVID-19 patients: the severity of pneumonia, in-hospital mortality, and the need for intensive care unit (ICU) admission. METHODS: This single-center study included 68 patients with laboratory- and radiologically-confirmed COVID-19 admitted to our emergency department. The study population was divided into patients with primary clinical out-comes (n = 32) and those without (n = 36). The need for ICU admission and/or in-hospital mortality were the primary clinical endpoints. The study group was also classified based on pneumonia severity: severe or mild/moderate. Blood samples were collected within 48 hours of admission to estimate serum galectin-3 concentrations. RESULTS: Multivariate regression analysis showed that lower concentrations of galectin-3 and arterial oxygen saturation (SpO2) were independently associated with the primary clinical outcomes (OR = 0.951, p = 0.035; OR = 0.862, p = 0.017, respectively); increased concentrations of galectin-3 were an independent predictor of severe pneumonia (OR = 1.087, p = 0.016). In the receiver operating characteristics curve analysis, serum galectin-3 concentrations at hospital admission predicted pneumonia severity with 52.1% sensitivity and 90% specificity with a cutoff of 38.76 ng/mL. CONCLUSIONS: Circulating galectin-3 at hospital admission could be a useful biomarker for identifying COVID-19 patients at high risk for severe pneumonia.

Gradual Versus Abrupt Reperfusion During Primary Percutaneous Coronary Interventions in ST-Segment-Elevation Myocardial Infarction (GUARD).

Background Intramyocardial edema and hemorrhage are key pathological mechanisms in the development of reperfusion-related microvascular damage in ST-segment-elevation myocardial infarction. These processes may be facilitated by abrupt restoration of intracoronary pressure and flow triggered by primary percutaneous coronary intervention. We investigated whether pressure-controlled reperfusion via gradual reopening of the infarct-related artery may limit microvascular injury in patients undergoing primary percutaneous coronary intervention. Methods and Results A total of 83 patients with ST-segment-elevation myocardial infarction were assessed for eligibility and 53 who did not meet inclusion criteria were excluded. The remaining 30 patients with totally occluded infarct-related artery were randomized to the pressure-controlled reperfusion with delayed stenting (PCRDS) group (n=15) or standard primary percutaneous coronary intervention with immediate stenting (IS) group (n=15) (intention-to-treat population). Data from 5 patients in each arm were unsuitable to be included in the final analysis. Finally, 20 patients undergoing primary percutaneous coronary intervention who were randomly assigned to either IS (n=10) or PCRDS (n=10) were included. In the PCRDS arm, a 1.5-mm balloon was used to achieve initial reperfusion with thrombolysis in myocardial infarction grade 3 flow and, subsequently, to control distal intracoronary pressure over a 30-minute monitoring period (MP) until stenting was performed. In both study groups, continuous assessment of coronary hemodynamics with intracoronary pressure and Doppler flow velocity was performed, with a final measurement of zero flow pressure (primary end point of the study) at the end of a 60-minute MP. There were no complications associated with IS or PCRDS. PCRDS effectively led to lower distal intracoronary pressures than IS over 30 minutes after reperfusion (71.2±9.37 mm Hg versus 90.13±12.09 mm Hg, P=0.001). Significant differences were noted between study arms in the microcirculatory response over MP. Microvascular perfusion progressively deteriorated in the IS group and at the end of MP, and hyperemic microvascular resistance was significantly higher in the IS arm as compared with the PCDRS arm (2.83±0.56 mm Hg.s.cm-1 versus 1.83±0.53 mm Hg.s.cm-1, P=0.001). The primary end point (zero flow pressure) was significantly lower in the PCRDS group than in the IS group (41.46±17.85 mm Hg versus 76.87±21.34 mm Hg, P=0.001). In the whole study group (n=20), reperfusion pressures measured at predefined stages in the early reperfusion period showed robust associations with zero flow pressure values measured at the end of the 1-hour MP (immediately after reperfusion: r=0.782, P<0.001; at the 10th minute: r=0.796, P<0.001; and at the 20th minute: r=0.702, P=0.001) and peak creatine kinase MB level (immediately after reperfusion: r=0.653, P=0.002; at the 10th minute: r=0.597, P=0.007; and at the 20th minute: r=0.538, P=0.017). Enzymatic myocardial infarction size was lower in the PCRDS group than in the IS group with peak troponin T (5395±2991 ng/mL versus 8874±1927 ng/mL, P=0.006) and creatine kinase MB (163.6±93.4 IU/L versus 542.2±227.4 IU/L, P<0.001). Conclusions In patients with ST-segment-elevation myocardial infarction, pressure-controlled reperfusion of the culprit vessel by means of gradual reopening of the occluded infarct-related artery (PCRDS) led to better-preserved coronary microvascular integrity and smaller myocardial infarction size, without an increase in procedural complications, compared with IS. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT02732080.

The relation of echo-derived lateral MAPSE to left heart functions and biochemical markers in patients with preserved ejection fraction: Short-term prognostic implications.

OBJECTIVE: Mitral annular plane systolic excursion (MAPSE) is a simple way to evaluate-left ventricle (LV) function. Our aim was to explain the relationship of MAPSE with LV function and biochemical markers in patients with preserved ejection fraction (EF), and to determine whether it has an effect on prognosis in echocardiography (echo) practice. METHODS: Consecutive patients referred to the echo laboratory between November 2020 and March 2021 were included in the study. In addition to conventional parameters, MAPSE of the lateral mitral annulus was measured in all patients. Patients were divided into three groups according to lateral MAPSE: low (<12 mm), relatively preserved (12-15 mm), and high (≥15 mm). RESULTS: A total of 512 patients with preserved EF were included in the study. MAPSE was low in 44 patients (9%), relatively preserved in 231 patients (45%), and high in 237 patients (46%). The mean age was higher in the low group compared to the other two groups (p < 0.001) and the body mass index was increased in the low group compared to the high group (p = 0.010). Atrial fibrillation and hypertension were more common in patients with low MAPSE. The rate of diastolic dysfunction (DD) and all-cause hospitalization were higher in the low and relatively preserved groups than in the high group (p < 0.001, p = 0.002; respectively). The pro-BNP level and mortality rate were higher in the low group compared to the relatively preserved and high groups (p = 0.007, p = 0.005; respectively). MAPSE was identified as independent predictor of hospitalization (OR: 0.284, 95% CI: 0.093-0.862, p = 0.026) via multivariate analysis and independent predictor of in-hospital mortality (HR: 0.002, 95% CI: 0-0.207, p = 0.008). CONCLUSIONS: Analysis of LV longitudinal function by echo-derived lateral MAPSE when LV ejection fraction is normal provides important information about DD and related heart failure and may predict prognosis in echo practice.

Intracardiac masses: Single center experience within 12 years: I-MASS Study.

Objective: The aim of this cross-sectional, retrospective, descriptive study was to review and classify cardiac masses systematically and to determine their frequencies. Methods: The medical records of 64,862 consecutive patients were investigated within 12 years. Every patient with a cardiac mass imaged by transthoracic echocardiography (TTE) and confirmed with an advanced imaging modality such as transesophageal echocardiography (TEE), computed tomography (CT) and/or cardiac magnetic resonance imaging (CMR) was included. Acute coronary syndromes triggering thrombus formation, vegetations, intracardiac device and catheter related thrombi were excluded. Results: Data demonstrated 127 (0.195%) intracardiac masses consisting of 33 (0.050%) primary benign, 3 (0.004%) primary malignant, 20 (0.030%) secondary tumors, 3 (0.004%) hydatid cysts and 68 (0.104%) thrombi respectively. The majority of primary cardiac tumors were benign (91.67%), predominantly myxomas (78.79%), and the less malignant (8.33%). Secondary cardiac tumors were common than the primary malignant tumors (20:3), with male dominancy (55%), lymphoma and lung cancers were the most frequent. Intracardiac thrombi was the majority of the cardiac masses, thrombi accompanying malignancies were in the first range (n = 17, 25%), followed by autoimmune diseases (n = 13, 19.12%) and ischemic heart disease with low ejection fraction (n = 12, 17.65%). Conclusions: This retrospective analysis identified 127 patients with cardiac masses. The majority of benign tumors were myxoma, the most common tumors that metastasized to the heart were lymphoma and lung cancers, and the thrombi associated with malignancies and autoimmune diseases were the most frequent.

Role of global longitudinal strain in discriminating variant forms of left ventricular hypertrophy and predicting mortality.

OBJECTIVE: In this study, we aimed to compare the functional adaptations of the left ventricle in variant forms of left ventricular hypertrophy (LVH) and to evaluate the use of two-dimensional speckle tracking echocardiography (2D-STE) in differential diagnosis and prognosis. METHODS: This was a prospective cohort study of 68 patients with LVH, including 20 patients with non-obstructive hypertrophic cardiomyopathy (HCM), 23 competitive top-level athletes free of cardiovascular disease, and 25 patients with hypertensive heart disease (HHD). All the subjects underwent 2D transthoracic echocardiography (TTE) and 2D-STE. The primary endpoint was all-cause mortality. Global longitudinal strain (GLS) below -12.5% was defined as severely reduced strain, -12.5% to -17.9% as mildly reduced strain, and above -18% as normal strain. RESULTS: The mean LV-GLS value was higher in athletes than in patients with HCM and HHD with the lowest value being in the HCM group (HCM: -11.4±2.2%; HHD: -13.6±2.6%; and athletes: -15.5±2.1%; p<0.001 among groups). LV-GLS below -12.5% distinguished HCM from others with 65% sensitivity and 77% specificity [area under curve (AUC)=0.808, 95% confidence interval (CI): 0.699-0.917, p<0.001]. The median follow-up duration was 6.4±1.1 years. Overall, 11 patients (16%) died. Seven of these were in the HHD group, and four were in the HCM group. The mean GLS value in patients who died was -11.8±1.5%. LV-GLS was significantly associated with mortality after adjusting age and sex via multiple analysis (RR=0.723, 95% CI: 0.537-0.974, p=0.033). Patients with GLS below -12.5% had a higher risk of all-cause mortality compared with that of patients with GLS above -12.5% according to Kaplan-Meier survival analysis for 7 years (29% vs. 9%; p=0.032). The LV-GLS value predicts mortality with 64% sensitivity and 70% specificity with a cut-off value of -12.5 (AUC=0.740, 95% CI: 0.617-0.863, p=0.012). CONCLUSION: The 2D-STE provides important information about the longitudinal systolic function of the myocardium. It may enable differentiation variable forms of LVH and predict prognosis.

Impairment of right ventricular longitudinal strain associated with severity of pneumonia in patients recovered from COVID-19.

Myocardial injury caused by COVID-19 was reported in hospitalized patients previously. But the information about cardiac consequences of COVID-19 after recovery is limited. The aim of the study was comprehensive echocardiography assessment of right ventricular (RV) in patients recovered from COVID-19. This is a prospective, single-center study. After recovery from COVID-19, echocardiography was performed in consecutive 79 patients that attended follow-up visits from July 15 to November 30, 2020. According to the recovery at home vs hospital, patients were divided into two groups: home recovery (n = 43) and hospital recovery (n = 36). Comparisons were made with age, sex and risk factor-matched control group (n = 41). In addition to conventional echocardiography parameters, RV global longitudinal strain (RV-GLS) and RV free wall strain (RV-FWS) were determined using 2D speckle-tracking echocardiography (2D STE). Of the 79 patients recovered from COVID-19, 43 (55%) recovered at home, while 36 (45%) required hospitalization. The median follow-up duration was 133  ±  35 (87-184) days. In patients recovered from hospital, RV-GLS and RV-FWS were impaired compared to control group (RV-GLS: -17.3  ±  6.8 vs. -20.4  ±  4.9, respectively [p = 0.042]; RV-FWS: -19.0  ±  8.2 vs. -23.4  ±  6.2, respectively [p = 0.022]). In subgroup analysis, RV-FWS was impaired in patients severe pneumonia (n = 11) compared to mild-moderate pneumonia (n = 28), without pneumonia (n = 40) and control groups (-15.8  ±  7.6 vs. -21.6  ±  7.6 vs. -20.8  ±  7.7 vs. -23.4  ±  6.2, respectively, [p = 0.001 for each]) and RV-GLS was impaired compared to control group (-15.2  ±  6.9 vs. -20.4  ±  4; respectively, [p = 0.013]). A significant correlation was detected between serum CRP level at hospital admission and both RV-GLS and RV-FWS (r = 0.285, p = 0.006; r = 0.294, p = 0.004, respectively). Age (OR 0.948, p = 0.010), male gender (OR 0.289, p = 0.009), pneumonia on CT (OR 0.019, p = 0.004), and need of steroid in treatment (OR 17.424, p = 0.038) were identifed as independent predictors of impaired RV-FWS (> -18) via multivariate analysis. We demonstrated subclinic dysfunction of RV by 2D-STE in hospitalized patients in relation to the severity of pneumonia after recovery from COVID-19. 2D-STE supplies additional information above standard measures of RV in this cohort and can be used in the follow-up of these patients.

Evaluation the relationship of left ventricular global longitudinal strain and laboratory parameters in discharged patients with COVID-19: a follow-up study.

BACKGROUND: The novel coronavirus infection (COVID-19) disease has spread rapidly and posed a great threat to global public health. The laboratory parameters and clinical outcomes of the disease in discharged patients remain unknown. In this study, we aimed to investigate the laboratory and echocardiographic findings of patients with COVID-19 after discharge and the relation between left ventricular global longitudinal strain (LVGLS) and inflammatory parameters in discharged patients. METHODS: A total of 75 patients recovering from COVID-19 as the study group were prospectively recruited from the COVID-19 outpatient clinic for their follow-up visits at a median 6 months after discharge. Patients were classified into groups according to pneumonia severity and impairment in LVGLS. Laboratory findings of patients both at admission and after discharge were evaluated and the relation with pneumonia severity at admission and LVGLS after discharge were analyzed. RESULTS: Serum ferritin, lactate dehydrogenase (LDH) and prohormone B-type natriuretic peptide (pro-BNP) levels after discharge were significantly higher in the study group than the control group (n = 44). Ferritin was found to be related to pneumonia severity. Serum ferritin and LDH values after discharge were significantly higher in patients with impaired LVGLS than those with preserved. There was a significant correlation between LVGLS, serum ferritin and LDH values after discharge (r = -0.252, p = 0.012; r = -0.268, p = 0.005, respectively). CONCLUSIONS: Clinicians should pay close attention to the serum ferritin and LDH levels in discharged patients for predicting the severity of COVID-19 disease and early identification of subclinical left ventricular myocardial dysfunction.

The Interplay between Features of Plaque Vulnerability and Hemodynamic Relevance of Coronary Artery Stenoses.

Fractional flow reserve (FFR) may not be immune from hemodynamic perturbations caused by both vessel and lesion related factors. The aim of this study was to investigate the impact of plaque- and vessel wall-related features of vulnerability on the hemodynamic effect of intermediate coronary stenoses. Methods and Results: In this cross-sectional study, patients referred to catheterization laboratory for clinically indicated coronary angiography were prospectively screened for angiographically intermediate stenosis (50-80%). Seventy lesions from 60 patients were evaluated. Mean angiographic stenosis was 62.1 ± 16.3%. After having performed FFR assessment, intravascular ultrasound (IVUS) was performed over the FFR wire. Virtual histology IVUS was used to identify the plaque components and thin cap fibroatheroma (TCFA). TCFA was significantly more frequent (65 vs. 38%, p = 0.026), and necrotic core volume (26.15 ± 14.22 vs. 16.21 ± 8.93 mm3, p = 0.04) was significantly larger in the positively remodeled than non-remodeled vessels. Remodeling index correlated with necrotic core volume (r = 0.396, p = 0.001) and with FFR (r = -0. 419, p = 0.001). With respect to plaque components, only necrotic core area (r = -0.262, p = 0.038) and necrotic core volume (r = -0.272, p = 0.024) were independently associated with FFR. In the multivariable model, presence of TCFA was independently associated with significantly lower mean FFR value as compared to absence of TCFA (adjusted, 0.71 vs. 0.78, p = 0.034). Conclusion: The current study demonstrated that for a given stenosis geometry, features of plaque vulnerability such as necrotic core volume, TCFA, and positive remodeling may influence the hemodynamic relevance of intermediate coronary stenoses.

Reducing Aortic Barotrauma and Vascular Extracellular Matrix Degradation by Pacemaker-Mediated QRS Widening.

Background The extent of pressure-related damage might be related to acceleration rate of the applied pressure (peak dP/dt) in the vascular system. In this study, we sought to determine whether dP/dt applied to the aortic wall (aortic dP/dt) and in turn vascular extracellular matrix degradation can be mitigated via modulation of left ventricular (LV) contractility (LV dP/dt) by pacemaker-mediated desynchronization. Methods and Results First, in 34 patients, changes in aortic dP/dt values in 3 aortic segments in response to pacemaker-mediated stepwise QRS widening leading to gradual desynchronization of the LV contraction by means of steadily changed atrioventricular delay (AVD) with temporary dual-chamber pacing was examined before and after beta-blocker (15 mg IV metoprolol) administration. Second, serum matrix metalloproteinase-9 levels were measured in the 20 patients with permanent pacemaker while they were on sinus rhythm with normal QRS width and 3 weeks after wide QRS rhythm ensured by dual pacing, dual sensing, and dual response to sensing with short AVD. LV dP/dt substantially correlated with dP/dt measured in ascending (r=0.83), descending (r=0.89), and abdominal aorta (r=0.96). QRS width strongly correlated with dP/dt measured in ascending (r=-0.95), descending (r=-0.92), and abdominal (r=-0.96) aortic segments as well. In patients with permanent pacemaker, wide QRS rhythm led to a significant reduction in serum matrix metalloproteinase-9 levels (from 142.5±32.9 pg/mL to 87.5±32.4 pg/mL [P<0.001]) at the end of 3 weeks follow-up. Conclusions QRS prolongation by short AVD dual pacing, dual sensing, and dual response to sensing results in concomitant decreases in peak dP/dt values in the LV and in all aortic segments with or without background beta-blocker administration, which in turn led to a significant reduction in circulating matrix metalloproteinase-9 levels. Registration URL: https://www.clini​caltr​ials.gov; Unique identifier: NCT03665558.

Influence of coronary calcification patterns on hemodynamic outcome of coronary stenoses and remodeling.

OBJECTIVE: The histological characteristics of plaque may affect the hemodynamic outcome of a given coronary stenosis. In particular, the potential effect of volumetric calcium content and the topographical distribution in the lesion segment on physiological outcome has not yet been investigated. The aim of this study was to identify any potential correlation between patterns of calcification and the fractional flow reserve (FFR) and the coronary remodeling index (RMI). METHODS: A total of 26 stable angina pectoris and 34 acute coronary syndrome patients without persistent ST-segment elevation constituted the study population. FFR was used to assess 70 intermediate coronary stenosis lesions. After obtaining hemodynamic measurements, quantitative grayscale and virtual histology-intravascular ultrasound analyses were performed. The depth, length, and circumferential distribution of calcification of the lesions were also recorded. RESULTS: Within the analyzed segment (area of interest, lesion segment), FFR was correlated with maximal thickness of deep calcification (r=-0.285; p=0.021) and calcification angle (r=-0.396; p=0.001). In lesions with a calcification angle >180°, the mean FFR value was significantly lower compared with those <180° (0.64±0.17 vs. 0.78±0.08; p=0.024). RMI was correlated with maximal angle of superficial (r=-0.437; p<0.001) and deep (r=0.425; p<0.001) calcification. RMI was correlated with maximal thickness of superficial (r=-0.357; p=0.003) and deep (r=0.417; p<0.001) calcification. RMI was also correlated with FFR (r=-0.477; p<0.001). CONCLUSION: This study demonstrated that the geometry, location, and amount of calcification of a plaque could affect hemodynamic and anatomical outcome measures in functionally significant stenoses by affecting vessel wall compliance.

Endocan: a novel biomarker associated with well-developed coronary collateral circulation in patients with stable angina and chronic total occlusion.

Angiogenesis and arteriogenesis have a crucial role in the formation of coronary collateral vessels. It has been shown that endocan and vascular cell adhesion molecule-1 (VCAM-1) are potential angiogenetic factors. We investigated the relationship between serum endocan levels and grade of coronary collaterals, and also the correlation of endocan levels with serum VCAM-1 levels. Patients with stable angina and at least one total coronary occlusion at invasive coronary angiography were included in our study. Collateral degree was graded according to Rentrop and Cohen's classification. Patients who had grade 0 or 1 collateral vessels were included in the poorly-developed collateral group, and those with grade 2 or 3 coronary collateral vessels were included in the well-developed collateral group. Serum endocan and VCAM-1 levels were significantly higher in the well-developed collateral group (436.6 ± 213.3 ng/mL vs. 216.1 ± 78.5 ng/mL, p < .001; 11.02 ± 6.58 ng/mL vs. 6.78 ± 1.14 ng/mL, p < .001, respectively). In a logistic regression analysis, only serum endocan level remained as an independent predictor for good collateral development. In the ROC curve analysis, 282 ng/mL endocan level had an a 82 % sensitivity and 86 % specificity for prediction of the well-developed collateral group. Higher endocan level was related to better coronary collateral development. In the event that these results are confirmed in further studies, endocan may be considered as an anti-ischemic treatment strategy in order to improve collateral development.

Bimodal Pattern of Coronary Microvascular Involvement in Diabetes Mellitus.

BACKGROUND: The contribution of functionally disturbed coronary autoregulation and structurally impaired microvascular vasodilatory function to reduced coronary flow velocity reserve, reflecting impaired coronary microcirculation in diabetes mellitus (DM), has not been clearly elucidated. The objective of this study was to identify the mechanism of coronary microvascular impairment in DM in relation to duration of disease. METHODS AND RESULTS: Coronary flow velocities in the anterior descending coronary artery were assessed by transthoracic echocardiography following angiography revealing normal epicardial coronary arteries in 55 diabetic and 47 nondiabetic patients. Average peak flow velocities, coronary flow velocity reserve, and microvascular resistance in baseline and hyperemic conditions (baseline and hyperemic microvascular resistance, respectively) were assessed. Reduced coronary flow velocity reserve in patients with short duration (<10 years) of DM compared with nondiabetic patients was primarily driven by increased baseline average peak flow velocity (26.50±5.6 versus 22.08±4.31, P=0.008) in the presence of decreased baseline microvascular resistance (3.69±0.86 versus 4.34±0.76, P=0.003). In contrast, decreased coronary flow velocity reserve in patients with long-standing (≥10 years) DM compared with nondiabetic patients was predominantly driven by reduced hyperemic average peak flow velocity (41.57±10.01 versus 53.47±11.8, P<0.001) due to increased hyperemic microvascular resistance (2.13±0.42 versus 1.69±0.39, P<0.001). CONCLUSIONS: Both altered coronary autoregulation and impaired microvascular vasodilatory function contribute to DM-related coronary microvascular impairment in a time-dependent manner. DM-induced early functional microvascular autoregulatory impairment seems to evolve into structural microvascular impairment in the initially overperfused microvascular territory at the later stage of disease.

A Mysterious Crescent in the Heart: Ruptured Sinus of Valsalva Dissecting Interatrial Septum, Multimodality Imaging, and Full Recovery.

A 59-year-old man who was admitted to the emergency department with new and spontaneous onset of fatigue, dyspnea, and palpitations. There was neither a history of trauma, chest pain, nor infection. Transthoracic two- and three-dimensional echocardiography and computer tomography demonstrated sinus of Valsalva aneurysm rupture dissecting interatrial septum and leading to a huge thrombus formation in it. The diagnosis with multimodality imaging performed within hours, and urgent surgery saved the patient's life.