Relation Between Coronary Tortuosity and Vasomotor Dysfunction in Patients Without Obstructed Coronaries?

Background: A large proportion of patients with angina and no obstructive coronary artery disease (ANOCA) has underlying coronary vasomotor dysfunction (CVDys), which can be diagnosed by a coronary function test (CFT). Coronary tortuosity is a common angiographic finding during the CFT. Yet, no data exist on the association between vasomotor dysfunction and coronary tortuosity.Aim: To investigate the association between CVDys and coronary tortuosity in patients with ANOCAMethods: All consecutive ANOCA patients who underwent clinically indicated CFT between February 2019 and November 2020 were included. CFT included acetylcholine spasm testing to diagnose epicardial or microvascular spasm, and adenosine testing to diagnose microvascular dysfunction (MVD). MVD was defined as an index of microvascular resistance (IMR) ≥ 25 and/or coronary flow reserve (CFR) <2.0. Coronary tortuosity, was scored (no, mild, moderate or severe) based on the angles of the curvatures in the left anterior descending (LAD) artery on angiography.Results: In total, 228 patients were included (86% female, mean age 56 ± 9 years). We found coronary artery spasm in 81% of patients and MVD in 45% of patients (15%: abnormal CFR, 30%: abnormal IMR). There were 73 patients with no tortuosity, 114 with mild tortuosity, 41 with moderate tortuosity, and no patients with severe tortuosity. No differences were found in cardiovascular risk factors or medical history, and the prevalence of CVDys did not differ between the no tortuosity, mild tortuosity and moderate tortuosity group (82, 82, and 85%, respectively).Conclusion: In this study, CVDys was not associated with coronary tortuosity. Future experimental and clinical studies on the complex interplay between coronary tortuosity, wall shear stress, endothelial dysfunction and coronary flow are warranted.

Analysis of Correlation Between Coronary Tortuosity and Calcification Score

Background: Coronary artery tortuosity (CAT) is regarded as a variation of vascular anatomy, and its relationship with coronary artery calcification (CAC) score is still not well clarified. Studying the correlation between coronary artery calcification scores and CAT to determine specific prevention and intervention populations seems to have more meaningful.Methods: The study is a cross-sectional retrospective study, including 1280 patients with tortuous coronary artery. CAT is defined as the presence of at least three consecutive curvatures of more than 45°measured during systole or diastole of a major epicardial coronary artery. Multivariable regression analysis was used to adjust the clinical parameters directly affecting CAT.Results: Of these individuals, 445 (35%) were evaluated having CAT, of which females are higher than males (59.1% vs. 40.9%). Moderate CAC score (101-400) (odds ratio (OR) 1.49, 95% confidence interval [95%CI] 1.05-2.10, P=0.025) revealed significantly associated with CAT on univariable analysis. However, multivariable analysis after adjusting for confounding factors only indicated that CAT was positively correlated with female (OR 1.60, 95%CI 1.22-2.10, P=0.001), hypertension (OR 1.34, 95% CI 1.03-1.74, P=0.028), and age (OR 1.04, 95% CI 1.01-1.03, P=0.001), while was negatively associated with body mass index (BMI) > 28 (OR 0.48, 95% CI 0.32-0.70, P<0.0001). Further analysis stratified by gender showed that compared with non-CAT, CAT was significantly linked with moderate CAC score (OR 1.79, 95% CI 1.00-3.20, P=0.048), hypertension (OR 1.54, 95% CI 1.07-2.22, P=0.021), and high-density lipoprotein (HDL) (OR 1.86, 95% CI 1.07-3.24, P=0.028), while was negatively related to BMI > 28 (OR 0.51, 95% CI 0.31-0.84, P<0.008) in female patients.Conclusions: CAT is more likely to be found in females, connected with hypertension, age, and BMI. No significant correlation is found between the presence of tortuosity and calcium score or diameter stenosis on multivariable analysis. Whereas the CAT is associated with moderate CAC score in correlation analysis when women are selected as the main group.

Angiographic profiles in patients of persistent non-valvular atrial fibrillation from a tertiary care center in north india

Funding Acknowledgements Type of funding sources: None. Background The relationship of atrial fibrillation (AF) with coronary artery disease (CAD) is well established. Atrial ischemia due to obstructive CAD has been identified as one of the key risk factors, leading to AF. However, sufficient evidence exists as to the presence of myocardial ischemia on stress imaging, even without the presence of obstructive CAD in AF patients. Slow flow and coronary tortuosity on angiogram can lead to downstream myocardial ischemia independent of CAD. Purpose We aimed to delineate the angiographic profiles in AF patients with attention to slow flow and tortuosity leading to ischemia in those without obstructive CAD. Methods The study was a nonrandomised, prospective, single-centre observational study of consecutive patients of persistent non valvular AF. Symptomatic patients despite optimal medical therapy (OMT) for 3 months were recruited and all underwent coronary angiograms (CAG). Patients with known CAD or prior history of myocardial infarction were excluded. Further angiographic analysis was done in those without obstructive CAD to determine incidence of slow flow (&gt;27 corrected TIMI frame count) and tortuosity (presence of ≥3 fixed bends in an epicardial artery). Results A total of 70 patients were recruited and followed for a mean duration of 12 ± 1.4 months. The mean age of the study group was 66.07 (±11.49). Hypertension (74%) was the commonest comorbidity followed by obesity (35%) and diabetes (30%). At CAG, 32/70 (45%) had obstructive CAD, 17/70 (24%) had non obstructive (&lt;50-70% stenosis) CAD and 21/70 (30%) had normal coronaries without atherosclerosis. Amongst patients without obstructive CAD (n = 38) slow flow was seen in 16/38 (42%) and coronary tortuosity in 11/38 (29%) patients. There ware no differences in terms of death, HF and FVR hospitalisations or stroke at follow up between the obstructive CAD vs no obstructive CAD. However in patients without obstructive CAD, hospitalisations for FVR was significantly increased in those having slow flow on CAG, 9/12 (75%) vs 7/26 (27%) in those without slow flow (p value = 0.005). The mean TIMI frame count was also significantly higher in those with FVR hospitalisations 35.3 ± 11 vs 25.8 ± 8.9 (p value = 0.005). TIMI frame count &gt;31 had a sensitivity of 83% and a specificity of 69% for predicting hospitalisations for FVR on ROC curve(AUC = 0.71). Conclusions CAD is closely related to AF and majority (70%) of our patients had evidence of atherosclerotic CAD on CAG in our study. A large proportion of patients with no evidence of obstructive CAD on CAG had slow flow or coronary tortuosity. Significantly increased hospitalisation for FVR seen in the slow flow group shows its significance and may lead to newer treatment modalities in future. Further larger studies looking at these aspects on CAG may give further insight as to the nature and prognosis of these entities.

Coronary tortuosity relation with carotid intima-media thickness, coronary artery disease risk factors, and diastolic dysfunction: is it a marker of early atherosclerosis?

Background Coronary tortuosity (C-Tor) is a common finding in coronary angiography (CAG). There are conflicting data about its link to atherosclerosis: one study found a negative relationship with coronary artery disease (CAD), although it had been linked to age and hypertension (HTN), which are CAD risk factors. Carotid intima-media thickness (C-IMT) is a measure of early atherosclerosis and a surrogate for CAD, diastolic dysfunction is also associated with CAD risk factors. In this retrospective case-control study, we investigated the relationship between C-Tor, C-IMT, diastolic dysfunction, and the other risk factors in patients undergoing CAG in a tertiary hospital between July 2017 and June 2018, after excluding patients with significant CAD. C-Tor was defined as the presence of ≥ 3 bends (≥ 45°) along the trunk of at least one main coronary artery in CAG. Results After excluding 663 patients due to exclusion criteria, 30 patients with C-Tor were compared with age and gender-matched controls. HTN was significantly more common in the C-Tor group (86.7% vs. 30%, p < 0.002); other clinical characteristics were similar. The C-IMT was abnormal in the C-Tor group only (p: 0.007). The diastolic dysfunction parameters differed between the two groups: the E/A ratio was < 1 in the C-Tor group and > 1 in the normal group (p: < 0.001); the E velocity and deceleration time were significantly lower in the C-Tor group (p: 0.001 and < 0.001 respectively); the E/E′ ratio, A, and A′ velocities were significantly higher (p: 0.005, < 0.001, < 0.001 respectively); while the S′ velocity was similar in the 2 groups (p: 0.078). The C-Tor group had higher total cholesterol and LDL (p: 0.003 and 0.006 respectively). All C-Tor patients undergoing stress tests had positive results. The only independent C-Tor predictors in a regression analysis were HTN, total cholesterol, A-wave velocity, and deceleration time (DT) (odds ratio: 14.7, 1.03, 1.15, and 0.95, all p: < 0.05). A-wave velocity had the best area under the curve, sensitivity, and specificity for C-Tor prediction (0.88, 73.3%, and 96.7% respectively) followed by DT (0.86, 66.67%, and 96.6% respectively). Conclusion C-Tor is associated with increased C-IMT, HTN, hyperlipidemia, and left ventricular diastolic dysfunction; all contributing to an ongoing atherosclerotic process. A-wave velocity and DT were independent predictors of C-Tor. C-Tor may cause microvascular ischemia that merits further investigation.

Impact of coronary artery tortuosity in ischemic and non-ischemic cardiovascular pathology

The aim of this paper was to review based on the existing literature the impact of coronary artery tortuosity on coronary pathology. Primarily, an attempt was made to establish the implication of coronary tortuosity as a physio-pathological mechanism of inducing ischemia in patients with non-obstructive coronary artery disease (CAD). Because the prevalence of tortuosity is higher in severe hypertensive patients, a second purpose of this paper was to review this association by understanding the physio-pathological processes and fluid dynamics in hypertrophic heart. Particularly, the effect of coronary tortuosity on systolic function with reference to longitudinal function and ventricular relaxation was addressed. Finally, were discussed- the technical difficulties imposed by coronary tortuosity to percutaneous coronary interventions.

Coronary Tortuosity Overestimate The FFR Measurement In Stenotic Coronary Artery Model

Background: The object of the study is to investigate the effect of coronary tortuosity (CT) on fractional flow reserve (FFR) in stenotic coronary artery.Methods: A three dimensional computational model of simulation of blood flow in stenotic coronary artery with multi-bend CT was constructed with Fluent 16.0 software. Blood was simulated as non-Newtonian fluid with the Carreau model. The simulation of blood flow in coronary artery stenotic model was used by the finite element methods with the condition of CT and no coronary tortuosity (NCT). Coronary artery hemodynamic parameters such as pressure, velocity and physiological diagnostic parameter fractional flow reserve (FFR) were studied in the model with the coronary tortuosity condition.Results: The results showed that the downstream CT impedance condition has significant impacts on numerical simulation. The pressure profile of pre-stenotic is almost identical in the two models. However the pressure in the pre-stenotic and post-stenotic artery domain is much higher in the CT model. The pressure fluctuation range in CT model was much higher than that in the NCT model. In the coronary artey model with 75% stenosis for the CT condition, the FFR was 0.823 while the FFR was 0.767 in the same model with NCT condition.Conclusions: This study provides evidence that FFR value was increased in coronary stenotic artery with the presence of CT. Therefore, it should be taking into account the influence of CT load effect in FFR measurement procedure, otherwise the CAD risk will be underestimated.

Coronary arteries in fibromuscular dysplasia. 3-Dimensional coronary CT, case-control study. The ARCARDIA-POL BIS study

Background Fibromuscular dysplasia (FMD) is a non-atherosclerotic arterial disease characterized by the presence of string-of-beads or focal stenosis. Other FMD-related lesions include arterial dissections, aneurysms, and tortuosity. However, limited data are available on the involvement of coronary arteries in pts diagnosed with “extra-coronary” FMD. Purpose To examine FMD-related coronary artery involvement, coronary artery lesions and coronary tortuosity in patients with a diagnosis of “extra-coronary” FMD. Methods In a case control study we enrolled 103 (age 45.7±13.2, 82 women) consecutive patients with a diagnosis of FMD, in whom atherosclerotic coronary artery disease was excluded on the basis of coronary CTA, and 96 (age 47.3±12.2, 75 women) sex- and age-matched controls without coronary atherosclerosis based on CTA imaging (Siemens Force 2x192 scanner). Detailed analysis of coronary arteries was assessed, with detailed analysis of arterial tortuosity, defined as curves &gt;30 OR &gt;45 OR &gt;90 degrees. Tortuosity Index (TI) was defined as number of curves x artery length (centerline) / vector artery start-end. Each arterial tortuosity evaluation was performed per coronary segment AND per artery. Size (area, length) of coronary arteries was also measured. Results Intravessel symmetry sign and cork-screw sign were more common in arteries of FMD patients than in controls (5.4% vs 1.3%, p&lt;0.001; 1.2% vs 0%, p=0.03, respectively). Number of arterial curves and TI of LAD, LCx and RCA were higher in FMD patients than in controls (arterial curves: p&lt;0.01 for all arteries – TI: 14.9 vs 8.5 for LAD, 9.8 vs 6.6 for LCX, and 11.2 vs 6.6 for RCA; p&lt;0.001 for all arteries). According to the segmental analysis, AUC under the ROC curve indicated the highest value for prediction of FMD for the number of curves (&gt;30 degrees) (0.777; 95% CI:0.713 to 0.833) or TI (0.794; 95% CI: 0.731 to 0.848), both in distal LAD. For the distal LAD indices, the best sensitivity and specificity values were for ≥4 curves (sens. 74%, spec. 72%) or for a TI &gt;5.6 (sens. 55%, spec. 94%), respectively. These predictive values were confirmed after correction for potential confounders. Interestingly, neither proximal LAD or proximal LCx number of curves or TI were related to FMD. No difference was found in terms of areas of coronary arteries between FMD patients and controls, with the only exception of LM (20.8±6.6 vs 17.9±5.8, p=0.002). Mean coronary artery lenght was significantly different between controls and patients with FMD (respectively LM 8.4±4.2 vs 9.8±4.5, p=0.022; LAD 117.8±28.6 vs 109.1±30.2, p=0.042; LCx 85.2±43.9 vs 62.9±31.4, p&lt;0.001; RCA 104.2±24.4 vs 115.7±25.8, p=0.002). No coronary aneurysms, ectasias or dissections were found in the examined cohort. Conclusions Distal and not proximal coronary arterial tortuosity is related to FMD. Coronary tortuosity defined as 4 distal LAD curves or a TI &gt;5.6 are highly specific for FMD. Funding Acknowledgement Type of funding source: None