Gulati, Rajiv

BACKGROUND: Myocardial infarction with nonobstructive coronary arteries (MINOCAs) and angina with nonobstructive coronary arteries (ANOCAs) present diagnostic and therapeutic challenges. We assessed the frequency of coronary microvascular disease (CMD) and its subtypes in MINOCA compared with ANOCA and evaluated long-term cardiovascular outcomes. METHODS: Patients with nonobstructive coronary arteries undergoing invasive coronary function testing from 2012 to 2022 were prospectively enrolled and retrospectively classified as MINOCA or ANOCA (reference group). Myocardial infarction due to atherothrombosis, myocarditis, and Takotsubo syndrome were excluded. Invasive provocation testing was performed. CMD was classified as endothelium-independent (coronary flow reserve <2.5 with adenosine) and endothelium-dependent (<50% increase in coronary blood flow with acetylcholine). Major adverse cardiovascular events (cardiac death, nonfatal myocardial infarction, heart failure hospitalization, urgent revascularization, stroke) were recorded over 8 years. RESULTS: Of 622 patients, 73 (12%) had MINOCA (69% female, median age 56 years) and 549 (88%) ANOCA (72% female, median age 53 years). CMD was common in both groups (71% versus 64%; P =0.271), while endothelium-independent CMD was more frequent in MINOCA (41% versus 21%; P <0.001). Over a median follow-up of 4.5 years, major adverse cardiovascular events occurred more often in MINOCA (40% versus 11%; adjusted hazard ratio, 2.4; P =0.001). CMD predicted higher major adverse cardiovascular events in both MINOCA (hazard ratio, 3.6 [95% CI, 1.1–12.0]; P =0.038) and ANOCA (hazard ratio, 7.9 [95% CI, 2.9–21.8]; P <0.001). CONCLUSIONS: CMD is common in both MINOCA and ANOCA. The higher prevalence of endothelium-independent CMD in MINOCA suggests a potential mechanistic role in infarction. Patients with MINOCA have a worse prognosis than ANOCA, particularly when CMD is present.

BACKGROUND: Randomized trials comparing radial and femoral access report access site crossover rates of 3% to 9% for radial access and 1% to 3% for femoral access. However, contemporary real-world crossover rates are not well characterized. The aim was to evaluate contemporary trends and predictors of vascular access site crossover during percutaneous coronary intervention (PCI). METHODS: We analyzed index PCI procedures recorded in the National Cardiovascular Data Registry CathPCI Registry from 2018 to 2024. Access site crossover was identified using documented access data, with radial-to-femoral crossover inferred when the final successful access site was femoral. Temporal trends and clinical predictors of crossover were examined. Operator experience was assessed using cumulative total and radial PCI volumes from 2011 to 2024 as captured in CathPCI Registry versions 4 and 5. RESULTS: Among 3 861 790 index PCIs, 192 902 (5.0%) involved access site crossover, with a modest increase over time. Radial-to-femoral crossover accounted for 81.2% of crossover events. Factors independently associated with crossover included older age, female sex, higher body mass index, and peripheral vascular disease. Operators with the lowest total PCI volume and the lowest radial PCI volume experienced the highest crossover rates. Notably, operators with low radial PCI volume demonstrated a substantial decline in radial-to-femoral crossover over the study period. CONCLUSIONS: In contemporary clinical practice, access site crossover rates are consistent with those reported in randomized trials. Although crossover occurs more frequently among lower-volume operators, rates decline with increasing operator experience, supporting the presence of a radial access learning curve and improvement in procedural performance over time.

BACKGROUND: The financial burden linked to the diagnosis and treatment of patients with chest pain on the health care system is considerable. Angina and nonobstructive coronary artery disease (ANOCA) is common, associated with adverse cardiovascular events, and may lead to repeat testing or hospitalizations. Diagnostic certainty can be achieved in patients with ANOCA using coronary reactivity testing (CRT); however, its financial effect on the patient has not been studied. Our goal was to assess the effect of CRT on health care–related cost in patients with ANOCA. METHODS: Patients with ANOCA who underwent diagnostic coronary angiography (CAG) and CRT (CRT group) were matched to controls who had similar presentation but only underwent a CAG without CRT (CAG group). Standardized inflation-adjusted costs were collected and compared between the 2 groups on an annual basis for 2 years post the index date (CRT or CAG). RESULTS: Two hundred seven CRT and 207 CAG patients were included in the study with an average age of 52.3±11.5 years and 76% females. The total cost was significantly higher in the CAG group as compared with the CRT group ($37 804 [$26 933–$48 674] versus $13 679 [$9447–$17 910]; P <0.001). When costs are itemized and divided based on the Berenson-Eggers Type of Service categorization, the largest cost difference occurred in imaging (any type, including CAG; P <0.001), procedures (eg, percutaneous coronary intervention/coronary artery bypass grafting/thrombectomy) ( P =0.001), and test (eg, blood tests, EKG; P <0.001). CONCLUSIONS: In this retrospective observational study, assessment of CRT in patients with ANOCA was associated with significantly reduced annual total costs and health care utilization. Therefore, the study may support the integration of CRT into clinical practice.

Background: There are good data to support using a single high-sensitivity cardiac troponin T (hs-cTnT) below the limit of detection of 5 ng/L to exclude acute myocardial infarction. Per the US Food and Drug Administration, hs-cTnT can only report to the limit of quantitation of 6 ng/L, a threshold for which there are limited data. Our goal was to determine whether a single hs-cTnT below the limit of quantitation of 6 ng/L is a safe strategy to identify patients at low risk for acute myocardial injury and infarction. Methods: The efficacy (proportion identified as low risk based on baseline hs-cTnT<6 ng/L) of identifying low-risk patients was examined in a multicenter (n=22 sites) US cohort study of emergency department patients undergoing at least 1 hs-cTnT (CV Data Mart Biomarker cohort). We then determined the performance of a single hs-cTnT<6 ng/L (biomarker alone) to exclude acute myocardial injury (subsequent hs-cTnT >99th percentile in those with an initial hs-cTnT<6 ng/L). The clinically intended rule-out strategy combining a nonischemic ECG with a baseline hs-cTnT<6 ng/L was subsequently tested in an adjudicated cohort in which the diagnostic performance for ruling out acute myocardial infarction and safety (myocardial infarction or death at 30 days) were evaluated. Results: A total of 85 610 patients were evaluated in the CV Data Mart Biomarker cohort, among which 24 646 (29%) had a baseline hs-cTnT<6 ng/L. Women were more likely than men to have hs-cTnT<6 ng/L (38% versus 20%, P <0.0001). Among 11 962 patients with baseline hs-cTnT<6 ng/L and serial measurements, only 1.2% developed acute myocardial injury, resulting in a negative predictive value of 98.8% (95% CI, 98.6–99.0) and sensitivity of 99.6% (95% CI, 99.5–99.6). In the adjudicated cohort, a nonischemic ECG with hs-cTnT<6 ng/L identified 33% of patients (610/1849) as low risk and resulted in a negative predictive value and sensitivity of 100% and a 30-day rate of 0.2% for myocardial infarction or death. Conclusions: A single hs-cTnT below the limit of quantitation of 6 ng/L is a safe and rapid method to identify a substantial number of patients at very low risk for acute myocardial injury and infarction.

Background: Coronary endothelial dysfunction (CED) causes angina/ischemia in patients with nonobstructive coronary artery disease (NOCAD). Patients with CED have decreased number and function of CD34+ cells involved in normal vascular repair with microcirculatory regenerative potential and paracrine anti-inflammatory effects. We evaluated safety and potential efficacy of intracoronary autologous CD34+ cell therapy for CED. Methods: Twenty NOCAD patients with invasively diagnosed CED and persistent angina despite maximally tolerated medical therapy underwent baseline exercise stress test, GCSF (granulocyte colony stimulating factor)-mediated CD34+ cell mobilization, leukapheresis, and selective 1×10 5 CD34+ cells/kg infusion into left anterior descending. Invasive CED evaluation and exercise stress test were repeated 6 months after cell infusion. Primary end points were safety and effect of intracoronary autologous CD34+ cell therapy on CED at 6 months of follow-up. Secondary end points were change in Canadian Cardiovascular Society angina class, as-needed sublingual nitroglycerin use/day, Seattle Angina Questionnaire scores, and exercise time at 6 months. Change in CED was compared with that of 51 historic control NOCAD patients treated with maximally tolerated medical therapy alone. Results: Mean age was 52±13 years; 75% were women. No death, myocardial infarction, or stroke occurred. Intracoronary CD34+ cell infusion improved microvascular CED (%acetylcholine-mediated coronary blood flow increased from 7.2 [−18.0 to 32.4] to 57.6 [16.3–98.3]%; P =0.014), decreased Canadian Cardiovascular Society angina class (3.7±0.5 to 1.7±0.9, Wilcoxon signed-rank test, P =0.00018), and sublingual nitroglycerin use/day (1 [0.4–3.5] to 0 [0–1], Wilcoxon signed-rank test, P =0.00047), and improved all Seattle Angina Questionnaire scores with no significant change in exercise time at 6 months of follow-up. Historic control patients had no significant change in CED. Conclusions: A single intracoronary autologous CD34+ cell infusion was safe and may potentially be an effective disease-modifying therapy for microvascular CED in humans. Registration: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03471611.