2024 Consensus Statement on Coronary Stenosis and Plaque Evaluation in CT Angiography From the Asian Society of Cardiovascular Imaging-Practical Tutorial (ASCI-PT).

The Asian Society of Cardiovascular Imaging-Practical Tutorial (ASCI-PT) is an instructional initiative of the ASCI School designed to enhance educational standards. In 2021, the ASCI-PT was convened with the goal of formulating a consensus statement on the assessment of coronary stenosis and coronary plaque using coronary CT angiography (CCTA). Nineteen experts from four countries conducted thorough reviews of current guidelines and deliberated on eight key issues to refine the process and improve the clarity of reporting CCTA findings. The experts engaged in both online and on-site sessions to establish a unified agreement. This document presents a summary of the ASCI-PT 2021 deliberations and offers a comprehensive consensus statement on the evaluation of coronary stenosis and coronary plaque in CCTA.

Diagnostic Performance of Cardiac CT and Transthoracic Echocardiography for Detection of Surgically Confirmed Bicuspid Aortic Valve: Effect of Calcium Extent and Valve Subtypes.

Purpose: This study aimed to compare the diagnostic performance of cardiac CT and transthoracic echocardiogram (TTE) depending on the degree of valvular calcification and bicuspid aortic valve (BAV) subtype. Materials and Methods: This retrospective study included 266 consecutive patients (106 with BAV and 160 with tricuspid aortic valve) who underwent cardiac CT and TTE before aortic valve replacement. Cardiac CT was used to evaluate the morphology of the aortic valve, and a calcium scoring scan was used to quantify valve calcium. The aortic valves were classified into fused and two-sinus types. The diagnostic accuracy of cardiac CT and TTE was calculated using a reference standard for intraoperative inspection. Results: CT demonstrated significantly higher sensitivity, negative predictive value, and accuracy than TTE in detecting BAV (p < 0.001, p < 0.001, and p = 0.003, respectively). The TTE sensitivity tended to decrease as valvular calcification increased. The error rate of TTE for CT was 10.9% for the two-sinus type of BAV and 28.3% for the fused type (p = 0.044). Conclusion: Cardiac CT had a higher diagnostic performance in detecting BAV than TTE and may help diagnose BAV, particularly in patients with severe valvular calcification.

The Prognostic Impact of Coronary Artery Disease and Aortic Aneurysm: Insights From CT Protocol for Simultaneous Evaluation of Coronary Artery and Aorta.

BACKGROUND: There is a strong correlation between risk factors for coronary artery disease (CAD) and aortic aneurysm (AA). We aimed to investigate the prevalence and prognostic impact of CAD and AA in patients who underwent coronary aorta computed tomography (CACT) protocol, which allowed simultaneous evaluation of coronary artery and aorta. METHODS: Between 2010 and 2021, 1,553 patients who underwent CACT were enrolled from a tertiary center. The presence and location of AA and the presence of CAD were identified from CT. The primary outcome was a composite of cardiovascular death, acute coronary syndrome requiring urgent revascularization, and stroke at 3 years after the index CT scan. RESULTS: Out of 1,553 enrolled patients, 179 (11.5%) had AA. The prevalence of CAD was significantly higher in patients with AA than those without (47.5% vs. 18.3%, P < 0.001). Among patients with AA, the prevalence of comorbid CAD was higher in those with abdominal AA than thoracic AA (57.3% vs. 37.8%, P = 0.014), respectively. In multivariable analysis, the presence of CAD was an independent predictor of primary outcome at 3 years (hazard ratio [HR], 2.58; 95% CI, 1.47-4.51; P = 0.001), while AA was not (HR, 1.00; 95% CI, 0.48-2.07; P = 0.993). CONCLUSION: In this cohort of patients undergoing simultaneous evaluation of coronary artery and aorta using CACT protocol, patients with AA had an increased risk of comorbid CAD compared to those without AA. CAD was independently associated with adverse clinical outcomes at 3 years.

Differential predictability for high-risk plaque characteristics between fractional flow reserve and instantaneous wave-free ratio.

To evaluate the differential associations of high-risk plaque characteristics (HRPC) with resting or hyperemic physiologic indexes (instantaneous wave-free ratio [iFR] or fractional flow reserve [FFR]), a total of 214 vessels from 127 patients with stable angina or acute coronary syndrome who underwent coronary computed tomography angiography (CCTA) and invasive physiologic assessment were investigated. HPRC were classified into quantitative (minimal luminal area < 4 mm2 or plaque burden ≥ 70%) and qualitative features (low attenuation plaque, positive remodeling, napkin ring sign, or spotty calcification). Vessels with FFR ≤ 0.80 or iFR ≤ 0.89 had significantly higher proportions of HRPC than those with FFR > 0.80 or iFR > 0.89, respectively. FFR was independently associated with both quantitative and qualitative HRPC, but iFR was only associated with quantitative HRPC. Both FFR and iFR were significantly associated with the presence of ≥ 3 HRPC, and FFR demonstrated higher discrimination ability than iFR (AUC 0.703 vs. 0.648, P = 0.045), which was predominantly driven by greater discriminating ability of FFR for quantitative HRPC (AUC 0.832 vs. 0.744, P = 0.005). In conclusion, both FFR and iFR were significantly associated with CCTA-derived HRPC. Compared with iFR, however, FFR was independently associated with the presence of qualitative HRPC and showed a higher predictive ability for the presence of ≥ 3 HRPC.

A Comparative Study of Thoracoscopic Left Atrial Appendage Clipping vs Stapled Resection.

BACKGROUND: The left atrial appendage (LAA) is the predominant site of thrombus formation in atrial fibrillation (AF), which is associated with ischemic stroke. This study comparatively evaluated the complete LAA closure rates between LAA clipping and stapled resections. METHODS: The study included 333 patients who underwent thoracoscopic operation with both preoperative and postoperative computed tomographic scans. Propensity score matching (4:1 ratio) was applied, matching 90 LAA clipping patients with 206 stapled resection patients. The primary end point was complete LAA closure, defined as a residual LAA depth of <1 cm on computed tomographic images obtained 1 year postoperatively. RESULTS: No 30-day death was observed. Complete LAA closure was achieved in 85.9% (286 of 333) of patients. After propensity score matching, the clipping group demonstrated a significantly higher complete LAA closure rate than the stapled resection group (95.6% vs 83.0%, P = .003). The residual LAA stump depth was also shorter in the clipping group compared with the stapled resection group (2.9 vs 5.3 mm, P = .001). Two patients with a residual LAA stump exhibited an association with ischemic stroke during follow-up. CONCLUSIONS: The clipping group demonstrated a higher rate of complete LAA closure compared with the stapled resection group. Close monitoring of patients with residual LAA stumps is essential. Further research with larger cohorts is needed to elucidate impact of the residual LAA stump on thromboembolic events.

Longitudinal Changes in the Myocardial T1 Relaxation Time, Extracellular Volume Fraction, and Left Ventricular Function in Asymptomatic Men.

(1) Background: Longitudinal changes in myocardial T1 relaxation time are unknown. We aimed to assess the longitudinal changes in the left ventricular (LV) myocardial T1 relaxation time and LV function. (2) Methods: Fifty asymptomatic men (mean age, 52.0 years) who underwent 1.5 T cardiac magnetic resonance imaging twice at an interval of 54 ± 21 months were included in this study. The LV myocardial T1 times and extracellular volume fractions (ECVFs) were calculated using the MOLLI technique (before and 15 min after gadolinium contrast injection). The 10-year Atherosclerotic Cardiovascular Disease (ASCVD) risk score was calculated. (3) Results: No significant differences in the following parameters were noted between the initial and follow-up assessments: LV ejection fraction (65.0 ± 6.7% vs. 63.6 ± 6.3%, p = 0.12), LV mass/end-diastolic volume ratio (0.82 ± 0.12 vs. 0.80 ± 0.14, p = 0.16), native T1 relaxation time (982 ± 36 vs. 977 ± 37 ms, p = 0.46), and ECVF (24.97 ± 2.38% vs. 25.02 ± 2.41%, p = 0.89). The following parameters decreased significantly from the initial assessment to follow-up: stroke volume (87.2 ± 13.7 mL vs. 82.6 ± 15.3 mL, p = 0.01), cardiac output (5.79 ± 1.17 vs. 5.50 ± 1.04 L/min, p = 0.01), and LV mass index (110.16 ± 22.38 vs. 104.32 ± 18.26 g/m2, p = 0.01). The 10-year ASCVD risk score also remained unchanged between the two timepoints (4.71 ± 0.19% vs. 5.16 ± 0.24%, p = 0.14). (4) Conclusion: Myocardial T1 values and ECVFs were stable over time in the same middle-aged men.

Pattern of pericardial calcification determines mid-term postoperative outcomes after pericardiectomy in chronic constrictive pericarditis.

OBJECTIVES: Although pericardiectomy is an effective treatment for constrictive pericarditis (CP), clinical outcomes are not always successful. Pericardial calcification is a unique finding in CP, although the amount and localization of calcification can vary. We investigated how the pattern and amount of pericardial calcification affect mid-term postoperative outcomes after pericardiectomy to treat CP. METHODS: All patients of total pericardiectomy in our hospital from 2010 to 2020 were enrolled. Preoperative Computed tomography (CT) scans of 98 consecutive patients were available and analyzed. Medical records were reviewed retrospectively. Cardiovascular events were defined as cardiovascular death or hospitalization associated with a heart failure symptom, and all-cause events were defined as any event that required admission. CT scans were analyzed, and the volume and localization pattern of peri-calcification were determined. Pericardium calcium scores are presented using Agatston scores. RESULTS: Of the 98 patients, 25 (25.5%) were hospitalized with heart failure symptoms after pericardiectomy. The median follow-up duration for all patients was 172 weeks. The group with a cardiovascular event had a lower calcium score than patients without an event. Multivariate Cox proportional analysis showed that high ln(calcium score+1) before pericardiectomy was a dependent predictor of cardiovascular event (hazard ratio, 0.90; p = 0.04) after pericardiectomy. When we set the cut-off value (ln(calcium score+1) = 7.22), there was a significant difference in cardiovascular events in the multivariate Cox proportional analysis (p = 0.04). CONCLUSION: A low burden of pericardial calcification was associated with a high rate of mid-term clinical events after pericardiectomy to treat CP.

Clinical outcomes of a CT protocol for simultaneous examination of the aorta and coronary artery in patients with aortic aneurysm.

Objectives: In patients with aortic aneurysm (AA), coronary artery disease (CAD) increases the risk of perioperative complications and even asymptomatic CAD is associated with adverse clinical outcomes. We aimed to compare coronary-aorta CT (CACT) with thoracoabdominal CT angiography (Aorta CT) for CAD management and clinical outcomes in these patients. Methods: We enrolled 479 patients undergoing CACT and 693 patients undergoing Aorta CT as an initial CT scan for AA. The primary outcome was a composite of all-cause death or myocardial infarction (MI) at 3 years after CT. The secondary outcomes were subsequent CAD management and invasive coronary angiography (CAG). Results: After index CT scan, the CACT group had a significantly higher rate of coronary revascularization compared with the Aorta CT group (10.7% vs. 3.8%, p < 0.001) but a lower probability of diagnostic CAG among total invasive CAG (32% vs. 55%, p < 0.001). At 3 months after the CT scan, the prescription rates of statins (65.8% vs. 44.6%, p < 0.001) and antiplatelet agents (57.6% vs. 43.9%, p < 0.001) were higher in the CACT group. During follow-up, the CACT group had a significantly lower incidence of the composite outcome of all-cause death or MI (adjusted HR 1.72, 95% CI 1.07-2.78, p = 0.027) than the Aorta CT group. Conclusion: Among patients with AA, CACT was associated with a higher rate of subsequent CAD management and a lower risk of all-cause death or MI compared to Aorta CT. When evaluating with AA using CT, simultaneous coronary and aortic evaluation using CACT would be recommended over Aorta CT.

Role of cardiovascular magnetic resonance imaging and cardiopulmonary exercise test in predicting composite clinical outcomes in patients with hypertrophic cardiomyopathy.

We aimed to evaluate the additive value of cardiovascular magnetic resonance imaging (CMR) and cardiopulmonary exercise test (CPET) to predict clinical outcomes in patients with HCM. We enrolled 373 patients with HCM and normal left ventricular systolic function who underwent CPET and CMR. The primary outcome was a clinical composite of all-cause death, cardiac transplantation, stroke, heart failure requiring hospitalization and defibrillator implantation. During a follow-up of 70.70 ± 30.74 months, there were 84 composite clinical events. Peak oxygen consumption during CPET was significantly lower (18.51±13.25 vs. 24.59±13.28 mL/kg/min, p < 0.001) and abnormal hemodynamic response to exercise was more frequently detected (41.7 vs. 20.8%, p<0.001) in the group with composite clinical events. The extent of late gadolinium enhancement was larger in the event group (15.39±10.53 vs. 11.97±9.53%LV, p<0.001). Selective parameters were added stepwise to conventional clinical parameters; the final model, where CPET and CMR parameters were added, was verified to have the highest increment value for clinical outcome prediction (p<0.001). This study demonstrated that CPET and CMR findings may be important clinical tools for risk stratification in HCM. Exercise capacity was an independent predictor of composite outcomes in patients with HCM, with incremental value as a risk factor when added to the alleged parameters. These findings could help physicians monitor and manage patients with HCM in the real clinical field.

Giant Coronary Artery Aneurysm with Thrombosis Complicated in a Patient with Idiopathic Hypereosinophilic Syndrome.

Idiopathic hypereosinophilic syndrome (iHES) is a rare systemic disease that is characterized by persistent peripheral eosinophilia (absolute eosinophil count ≥1500/uL) for more than 6 months, with end-organ damage and absence of a primary cause for eosinophilia. Coronary artery aneurysm (CAA) is a rare but life-threatening complication. Here, we report a case of CAA with thrombosis in a patient with iHES in whom the disease activity was well-controlled (eosinophil count <500/uL) for several years. Despite modest control of the disease activity, giant CAA can be associated with iHES; and therefore, close surveillance and monitoring for the development of complications is warranted.

Different characteristics of apical aneurysm in hypertrophic cardiomyopathy are related to difference in long-term prognosis.

BACKGROUND: Data regarding long-term cardiac and cerebrovascular adverse events in patients with hypertrophic cardiomyopathy (HCM) and apical aneurysm (AAn) are scarce and specific treatment strategies that include the use of anticoagulants have not yet been established. We aimed to evaluate the prevalence and long-term prognostic implication based on characteristics of AAn in patients with HCM. METHODS: A total of 458 consecutive patients diagnosed with HCM underwent cardiovascular magnetic resonance imaging and echocardiography from August 1, 2008 to December 31, 2015. AAn was classified into Grade 1 and Grade 2 based on size and morphology. The patients were followed up for a median duration of 6.3 years (range, 4.2-8.7 years) for major adverse cardiac and cerebral events (MACCEs); a composite of cardiac death, HCM-related hospitalization, cerebrovascular accident (CVA), heart transplantation, myocardial infarction, and implantable cardiac defibrillator/cardiac resynchronization therapy. RESULTS: AAn was detected in 9.2%. MACCEs developed more frequently in patients with AAn than in those without AAn (30.1% vs. 20.7%, P = 0.015), with the rate of CVA as the main difference (9.7% vs. 5.3%, P = 0.011). Grade 2 AAn group showed significantly higher MACCE than Grade 1 AAn group (41.8% vs. 21.9%, P < 0.001). In multivariate analysis, the presence of AAn was independently associated with increased risk of MACCEs (adjusted hazard ratio: 1.95; 95% confidence interval, CI: 1.16-3.28; P = 0.012). CONCLUSIONS: AAn is independently associated with increased risk of HCM-related adverse events, especially cerebral infarction, with significant relationship between aneurysm size and adverse events.

Risk factors and clinical effects of subclinical leaflet thrombosis after transcatheter aortic valve replacement.

Aims: The number of trans-catheter aortic valve replacement (TAVR) procedure is increasing; However, the incidence of leaflet thrombosis is higher in TAVR than in surgical aortic valve replacement (SAVR). In this study, the risk factors for leaflet thrombosis after TAVR and its effects on hemodynamics and clinical course were investigated. Methods and results: Multidetector computed tomography (MDCT) was performed at 1year after TAVR in 94 patients from January 2015 to October 2020 at Samsung Medical Center in South Korea. Among the 94 patients, subclinical leaflet thrombosis occurred in 20 patients, and risk factors were analyzed. In addition, the difference in aortic valve (AV) hemodynamics between the two groups was examined and clinical outcomes compared. Indexed mean sinus of Valsalva (SOV) diameter, AV calcium volume, and post-procedure effective orifice area (EOA) were predictive of subclinical leaflet thrombosis with the area under the curve (AUC) value of 0.670 (P-value = 0.020), 0.695 (P-value = 0.013), and 0.665 (P-value = 0.031), respectively. In echocardiography performed at the time of follow-up CT, the value of AV max velocity and AV mean pressure gradient were higher in the thrombosis group and the EOA and Doppler velocity index values were lower in the thrombosis group than in the no thrombosis group. Clinical outcome was not significantly different between the two groups (log-rank P-value = 0.26). Conclusion: Larger indexed SOV diameter, higher AV calcium volume, and smaller post-procedure AV EOA were risk factors for subclinical leaflet thrombosis after TAVR. Subclinical leaflet thrombosis has a benign course when properly managed.

A Primary Neuroendocrine Tumor Mimicking a Thrombus in the Left Atrial Appendage.

Most cardiac tumors are metastases, and primary cardiac tumors are rare; even among primary cardiac tumors, primary cardiac neuroendocrine tumors (NETs) are extremely rare. Herein, we report a case of a patient presenting a left atrial mass without past medical history. Because of the location and movement of the mass, as well as the patient's cerebral infarction episode, the mass was initially suspected to be a thrombus. However, the mass was surgically diagnosed as NET.

Significance of transesophageal contrast echocardiography with the agitated saline test for diagnosing pulmonary arteriovenous malformations.

Objectives: This study evaluated the diagnostic value of transesophageal contrast echocardiography (TECE) with the agitated saline test for diagnosing pulmonary arteriovenous malformations (PAVMs) in comparison with chest CT or pulmonary angiography. Background: Although transthoracic contrast echocardiography (TTCE) is the recommended screening test for diagnosing PAVMs, it has low specificity and positive predictive value. TECE is expected to offer improved sensitivity and specificity compared with TTCE, but no studies have reported the diagnostic accuracy and clinical significance of TECE in detecting PAVMs. Methods and results: In total, 1,809 patients underwent TECE with the agitated saline test to evaluate symptoms of a suspected right to left shunt. Patients with hereditary hemorrhagic telangiectasia (HHT) were excluded. A total of 387 patients showed transpulmonary bubble passage, indicating a PAVM. Among them, 182 patients had additional chest CT or pulmonary angiography. Those patients were divided into two groups according to the presence of a PAVM in the radiologic imaging. A total of 18 patients (9.8%) were confirmed for the PAVM group. Only 13 patients required embolization for their PAVMs. The TECE with saline test results were divided into four grades according to the number of bubbles: grade 1 (n = 91), grade 2 (n = 47), grade 3 (n = 35), and grade 4 (n = 9). None of the patients in the PAVM group had grade 1 shunts in their TECE results. The positive predictive values for the presence of a PAVM according to the TECE grade scale were 10.6% for grade 2, 22.8% for grade 3, and 55.6% for grade 4. Conclusion: TECE with a grade scale is a useful method for initially diagnosing PAVMs in non-HHT patients with a suspected right to left shunt. The findings of this study also suggest that patients with a small grade (<10 bubbles) shunt in their TECE findings should be spared unnecessary radiation exposure from CT scans or pulmonary angiography.

Comparison of diagnostic performance between dynamic versus static adenosine-stress myocardial CT perfusion to detect hemodynamically significant coronary artery stenosis: A prospective multicenter study.

Myocardial computed tomography perfusion (CTP) imaging is a noninvasive method for detecting myocardial ischemia. This study aimed to compare the diagnostic performance of dynamic and static adenosine-stress CTPs for detecting hemodynamically significant coronary stenosis. We prospectively enrolled 42 patients (mean age, 59.7 ± 8.8 years; 31 males) with ≥40% coronary artery stenosis. All patients underwent dynamic CTP for adenosine stress. The static CTP was simulated by choosing the seventh dynamic dataset after the initiation of the contrast injection. Diagnostic performance was compared with invasive fractional flow reserve (FFR) <0.8 as the reference. Of the 125 coronary vessels in 42 patients, 20 (16.0%) in 16 (38.1%) patients were categorized as hemodynamically significant. Dynamic and static CTP yielded similar diagnostic accuracy (90.4% vs 88.8% using visual analysis, P = .558; 77.6% vs 80.8% using quantitative analysis, P = .534; 78.4% vs 82.4% using combined visual and quantitative analyses, P = .426). The diagnostic accuracy of combined coronary computed tomography angiography (CCTA) and dynamic CTP (89.6% using visual analysis, P = .011; 88.8% using quantitative analysis, P = .018; 89.6% using combined visual and quantitative analyses, P = .011) and that of combined CCTA and static CTP (88.8% using visual analysis, P = .018; 90.4% using quantitative analysis, P = .006; 91.2% using combined visual and quantitative analyses, P = .003) were significantly higher than that of CCTA alone (77.6%). Dynamic CTP and static CTP showed similar diagnostic performance in the detection of hemodynamically significant stenosis.

T1 values and extracellular volume fraction in asymptomatic subjects: variations in left ventricular segments and correlation with cardiovascular risk factors.

To evaluate variations in pre-contrast (preT1) and post-contrast (postT1) myocardial T1 values and extracellular volume fraction (ECV) according to left ventricular (LV) segments and to find correlations between them and cardiovascular risk factors. The 233 asymptomatic subjects (210 men, 23 women; aged 54.1 ± 6.0 years) underwent cardiac magnetic resonance imaging with preT1 and postT1 mapping on a 1.5-T scanner. T1 values and ECVs were evaluated according to LV segments, age, sex, and estimated glomerular filtration rate (eGFR). Based on the presence of hypertension (HTN) and diabetes mellitus (DM), subjects were subdivided into the control, HTN, DM, and HTN and DM (HTN-DM) groups. T1 values and ECV showed significant differences between septal and lateral segments at the mid-ventricular and basal levels (p ≤ 0.003). In subgroup analysis, the HTN-DM group showed a significantly higher ECV (0.260 ± 0.023) than the control (0.240 ± 0.021, p = 0.011) and HTN (0.241 ± 0.024, p = 0.041) groups. Overall postT1 and ECV of the LV had significant correlation with eGFR (r = 0.19, p = 0.038 for postT1; r = - 0.23, p = 0.011 for ECV). Septal segments show higher preT1 and ECV but lower postT1 than lateral segments at the mid-ventricular and basal levels. ECV is significantly affected by HTN, DM, and eGFR, even in asymptomatic subjects.

Anatomic and Hemodynamic Plaque Characteristics for Subsequent Coronary Events.

Objectives: While coronary computed tomography angiography (CCTA) enables the evaluation of anatomic and hemodynamic plaque characteristics of coronary artery disease (CAD), the clinical roles of these characteristics are not clear. We sought to evaluate the prognostic implications of CCTA-derived anatomic and hemodynamic plaque characteristics in the prediction of subsequent coronary events. Methods: The study cohort consisted of 158 patients who underwent CCTA with suspected CAD within 6-36 months before percutaneous coronary intervention (PCI) for acute myocardial infarction (MI) or unstable angina and age-/sex-matched 62 patients without PCI as the control group. Preexisting high-risk plaque characteristics (HRPCs: low attenuation plaque, positive remodeling, napkin-ring sign, spotty calcification, minimal luminal area <4 mm2, or plaque burden ≥70%) and hemodynamic parameters (per-vessel fractional flow reserve [FFRCT], per-lesion ΔFFRCT, and percent ischemic myocardial mass) were analyzed from prior CCTA. The primary outcome was a subsequent coronary event, which was defined as a composite of vessel-specific MI or revascularization for unstable angina. The prognostic impact of clinical risk factors, HRPCs, and hemodynamic parameters were compared between vessels with (160 vessels) and without subsequent coronary events (329 vessels). Results: Vessels with a subsequent coronary event had higher number of HRPCs (2.6 ± 1.4 vs. 2.3 ± 1.4, P = 0.012), lower FFRCT (0.76 ± 0.13 vs. 0.82 ± 0.11, P < 0.001), higher ΔFFRCT (0.14 ± 0.12 vs. 0.09 ± 0.08, P < 0.001), and higher percent ischemic myocardial mass (29.0 ± 18.5 vs. 26.0 ± 18.4, P = 0.022) than those without a subsequent coronary event. Compared with clinical risk factors, HRPCs and hemodynamic parameters showed higher discriminant abilities for subsequent coronary events with ΔFFRCT being the most powerful predictor. HRPCs showed additive discriminant ability to clinical risk factors (c-index 0.620 vs. 0.558, P = 0.027), and hemodynamic parameters further increased discriminant ability (c-index 0.698 vs. 0.620, P = 0.001) and reclassification abilities (NRI 0.460, IDI 0.061, P < 0.001 for all) for subsequent coronary events. Among vessels with negative FFRCT (>0.80), adding HRPCs into clinical risk factors significantly increased discriminant and reclassification abilities for subsequent coronary events (c-index 0.687 vs. 0.576, P = 0.005; NRI 0.412, P = 0.002; IDI 0.064, P = 0.001) but not for vessels with positive FFRCT (≤0.80). Conclusion: In predicting subsequent coronary events, both HRPCs and hemodynamic parameters by CCTA allow better prediction of subsequent coronary events than clinical risk factors. HRPCs provide more incremental predictability than clinical risk factors alone among vessels with negative FFRCT but not among vessels with positive FFRCT. Clinical Trial Registration: PreDiction and Validation of Clinical CoursE of Coronary Artery DiSease With CT-Derived Non-INvasive HemodYnamic Phenotyping and Plaque Characterization (DESTINY Study), NCT04794868.

Functional angiography-derived index of microcirculatory resistance validated with microvascular obstruction in cardiac magnetic resonance after STEMI.

INTRODUCTION AND OBJECTIVES: The index of microcirculatory resistance (IMR) measured after primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) is associated with microvascular obstruction (MVO) and adverse clinical events. To evaluate MVO after successful primary PCI for STEMI without pressure wires or hyperemic agents, we investigated the feasibility and usefulness of functional angiography-derived IMR (angio-IMR). METHODS: The current study included a total of 285 STEMI patients who underwent primary PCI and cardiac magnetic resonance (CMR). Angio-IMR of the culprit vessel after successful primary PCI was calculated using commercial software. MVO, infarct size, and myocardial salvage index were assessed using CMR, which was obtained a median of 3.0 days [interquartile range, 3.0-5.0] after primary PCI. RESULTS: Among the total population, 154 patients (54.0%) showed elevated angio-IMR (> 40 U) in the culprit vessel. MVO was significantly more prevalent in patients with angio-IMR> 40 U than in those with angio-IMR ≤ 40 U (88.3% vs 32.1%, P <.001). Infarct size, extent of MVO, and area at risk were significantly larger in patients with angio-IMR> 40 U than in those with angio-IMR ≤ 40 U (P <.001 for all). Angio-IMR showed a significantly higher discriminatory ability for the presence of MVO than thrombolysis in myocardial infarction flow grade or myocardial blush grade (area under the curve: 0.821, 0.504, and 0.496, respectively, P <.001). CONCLUSIONS: Angio-IMR was significantly associated with CMR-derived infarct size, extent of MVO, and area at risk. An elevated angio-IMR (> 40 U) after primary PCI for STEMI was highly predictive of the presence of MVO in CMR. This trial was registered at ClnicalTrialsgov (Identifier: NCT04828681).

Determinants of Exercise Capacity in Patients With Hypertrophic Cardiomyopathy.

BACKGROUND: Reduced exercise capacity reflects symptom severity and clinical outcomes in patients with hypertrophic cardiomyopathy (HCM). The present study aimed to identify factors that may affect exercise capacity in patients with HCM. METHODS: In 294 patients with HCM and preserved left ventricular (LV) ejection fraction, we compared peak oxygen consumption (peak VO2) evaluated by cardiopulmonary exercise testing as a representative parameter of exercise tolerance with clinical and laboratory data, including N-terminal pro-hormone of brain natriuretic peptide (NT-proBNP), diastolic parameters on echocardiography, and the grade of myocardial fibrosis on cardiac magnetic resonance imaging (CMR). RESULTS: Median peak VO2, was 29.0 mL/kg/min (interquartile range [IQR], 25.0-34.0). Age (estimated ß = -0.140, P < 0.001), female sex (ß = -5.362, P < 0.001), NT-proBNP (ß = -1.256, P < 0.001), and E/e' ratio on echocardiography (ß = -0.209, P = 0.019) were significantly associated with exercise capacity. Peak VO2 was not associated with the amount of myocardial fibrosis on CMR (mean of late gadolinium enhancement 12.25 ± 9.67%LV). CONCLUSION: Decreased exercise capacity was associated with age, female sex, increased NT-proBNP level, and E/e' ratio on echocardiography. Hemodynamic changes and increased filling pressure on echocardiography should be monitored in this population for improved outcomes.