Circulation: Cardiovascular Imaging最新文献

Background: Lp(a) (lipoprotein [a]) and coronary artery calcium score (CACS) are independently associated with atherosclerotic cardiovascular disease (ASCVD) risk. This study aimed to investigate sex-specific prognostic differences between Lp(a) and CACS in ASCVD risk.

Methods: We analyzed 4651 participants from the Multi-Ethnic Study of Atherosclerosis, grouped by sex. Multivariable Cox regression analysis was performed to evaluate the prognostic value of Lp(a) and CACS for ASCVD risk in both sexes. The predictive performance of these factors was compared in men and women.

Results: During a median follow-up of 13.84 years, 465 ASCVD events were recorded (272 in men and 193 in women). Multivariable Cox regression analysis revealed that both elevated Lp(a) and CACS were independent predictors of ASCVD risk in both sexes. The C-index analysis demonstrated that CACS provided incremental prognostic value over Lp(a) in men (C-index: 0.732 versus 0.714; P=0.011), but not in women (C-index: 0.776 versus 0.762; P=0.069). Notably, in men with CACS >400, elevated Lp(a) levels (adjusted hazard ratio, 1.822 [95% CI, 1.041-3.189]; P=0.036) were associated with higher ASCVD risk, although no such association was observed in those with CACS ≤400. In women, elevated Lp(a) levels were associated with increased ASCVD risk in those with CACS >100 (adjusted hazard ratio, 1.877 [95% CI, 1.130-3.118]; P=0.015).

Conclusions: Although both Lp(a) and CACS independently predict ASCVD risk in both sexes, the predictive value of Lp(a) varies significantly between men and women across different CACS categories. These findings may inform sex-specific strategies for primary prevention of ASCVD.

Background: The prognostic utility of quantitative positron emission tomography (PET) with myocardial blood flow (MBF) measurements in patients with prior coronary artery bypass grafting remains unestablished. We evaluated PET-derived myocardial flow reserve (MFR) and coronary vascular resistance (CVR) for risk stratification in patients who have undergone coronary artery pass grafting.

Methods: This retrospective study included consecutive patients undergoing Rubidium-82 PET myocardial perfusion imaging between May 2017 and November 2023. MFR and CVR were defined as the ratio of stress to rest myocardial blood flow and mean arterial pressure divided by stress myocardial blood flow, respectively. The primary end point was major adverse cardiovascular events (MACE), defined as a composite of cardiac mortality and nonfatal myocardial infarction. The secondary end point (expanded MACE) included MACE plus hospitalization for unstable angina or heart failure. Associations were assessed using multivariable Cox proportional hazards models after adjusting for clinical variables and PET parameters.

Results: A total of 556 patients (median age 72 years, 79% male) were included. Over a median follow-up of 676 (482-1077) days, 39 patients (7.0%) experienced MACE, and 74 (13.3%) experienced expanded MACE. Receiver operating characteristic analysis identified optimal cutoff values of 2.05 for MFR and 66.4 mm Hg·min·g/mL for CVR. Impaired MFR and CVR were each significantly associated with increased rates of MACE and expanded MACE (all P<0.001). Stratification by combined MFR and CVR status demonstrated significant differences in event rates across groups (all P<0.001). In multivariable analysis, MFR (≤2.05), CVR (≥66.4 mm Hg·min·g/mL), and their combination were all independently associated with MACE, with adjusted hazard ratio of 2.954 ([95% CI, 1.287-6.780]; P=0.011), 2.356 ([95% CI, 1.075-5.161]; P=0.032), and 5.437 ([95% CI, 2.700-10.950]: P<0.001), respectively.

Conclusions: PET-derived MFR and CVR provide independent and incremental prognostic value in coronary artery bypass grafting patients, enhancing risk stratification beyond conventional perfusion and function parameters.

Background: Myocardial late gadolinium enhancement (LGE) using cardiac magnetic resonance imaging has been described in older endurance athletes, particularly at the ventricular hinge point. However, data on young, elite athletes are lacking. We therefore quantified the prevalence of hinge point LGE (HP-LGE) in young elite-level athletes.

Methods: We investigated 309 (40% women; median age 25.1 [21.9-29.5] years) asymptomatic athletes included in the ELITE prospective cohort (Evaluation of Lifetime Participation in Intensive Top-level Sports and Exercise cohort), investigating cardiovascular screenings of elite (national-, international-, Olympic-, or Paralympic-) level athletes, including cardiac magnetic resonance imaging with short-axis cine imaging, LGE, and T1-mapping.

Results: A total of 124 (40%) athletes had HP-LGE, with a higher prevalence in men compared with women (47% versus 30%; P=0.004). When indexed for body surface area, athletes with HP-LGE had greater left ventricle end-systolic volumes (53±11 mL/m² versus 51±11 mL/m²; P=0.037), right ventricle end-systolic volumes (56±12 mL/m² versus 53±11 mL/m²; P=0.020), lower left ventricle ejection fraction (55.5±5.0% versus 56.7±4.6%; P=0.035), lower right ventricle ejection fraction (53.9±5.0% versus 55.2±4.4%; P=0.021), and smaller estimated global left ventricle extracellular volumes (24.45±2.52% versus 25.27±2.59%; P=0.015). In multivariable regression analyses, male sex was strongly associated with HP-LGE (odds ratio, 3.07 [95% CI, 1.32-7.32]; P=0.010).

Conclusions: HP-LGE is a common finding in asymptomatic, elite athletes and is strongly associated with sex. Lower left ventricle ejection fraction is moderately associated with HP-LGE. Our study's HP-LGE prevalence indicates that HP-LGE should be interpreted as a feature of the athlete's heart.

Background: Assessment of the systemic right ventricle (RV) is critical for patients with hypoplastic left heart syndrome (HLHS). Traditional imaging metrics fail to capture the RV's complex geometry and remodeling in HLHS, limiting risk stratification. We aimed to apply statistical shape modeling to a large multicenter cohort of cardiac magnetic resonance data sets to define RV shape variants and evaluate associations with clinical outcomes.

Methods: Cardiac magnetic resonance from the FORCE (Fontan Outcomes Registry Using CMR Examinations) was analyzed for patients with HLHS post-Fontan. Three-dimensional RV models were segmented at end-diastole and processed using statistical shape modeling (ShapeWorks). Shape modes were extracted via principal component analysis and correlated with RV function, tricuspid regurgitation, remnant left ventricular morphology, and clinical outcomes, including mortality, transplant, and a composite adverse outcome including heart failure.

Results: The mean RV shape template of 329 patients with HLHS (mean age, 14.7±6.3 years) depicted a circumferentially dilated RV with loss of septal concavity. RV end-diastolic volume was independently associated with composite adverse outcome (odds ratio, 6.50; P=0.001). Distinct shape modes were identified, including an apical bulge phenotype that was independently associated with composite adverse outcome (odds ratio, 2.45; P=0.047) and mortality/transplant (odds ratio, 4.24; P=0.004). This variant also correlated with RV dilation, hypertrophy, and impaired regional strain. A spheroidal shape was associated with ≥moderate tricuspid regurgitation and tricuspid annular dilation. Remnant left ventricular morphology influenced RV shape and function but not transplant-free survival.

Conclusions: Our statistical shape modeling analyses provide novel insights into RV geometric remodeling in HLHS and identify specific shape phenotypes associated with dysfunction and adverse outcomes. Shape-based metrics offer additive prognostic value beyond conventional volumetric analysis, with potential implications for risk stratification and surgical decision-making in single-ventricle physiology.