Sudanese Angiography Study Finds Women’s Coronary Arteries Are Longer and More Tapered Than Men’s

Women undergoing coronary angiography in Sudan show markedly different left coronary artery anatomy from men, according to a retrospective multicentre study of 357 angiograms that measured the left anterior descending (LAD) and left circumflex (LCX) arteries in patients with non-obstructive coronary artery disease. In the cohort, females had significantly longer LAD arteries, greater overall tapering, and a stronger correlation between vessel diameter and length than males, and sex remained independently associated with LAD length and tapering even after statistical adjustment for age and body surface area. The study, published in Artery Research, was designed to address a persistent gap in the coronary morphometry literature, in which existing anatomical benchmarks have been derived largely from Western and male-dominant populations while African cohorts remain underrepresented.

The research team analyzed coronary angiograms collected between July 2018 and August 2019 at three Sudanese cardiac centers: Khartoum Hospital, Sudan Heart Center, and Al-Zaytouna Specialist Hospital. All patients had been referred for elective angiography for suspected ischemia and had non-obstructive coronary artery disease, defined as stenosis of less than 50 percent. The final cohort comprised 147 males and 210 females, with a mean age of 55.3 years. Patients with obstructive coronary disease, prior revascularization with stents or bypass grafts, congenital heart disease, or contrast hypersensitivity were excluded, so that the measurements would reflect anatomical variation rather than the effects of advanced atherosclerosis or procedural artifacts.

Measurement methods were deliberately standardized. Angiograms were acquired through radial artery access using 5-French catheters, and nitroglycerin was administered before imaging according to each center’s protocol to minimize coronary vasospasm that could distort vessel diameters. Quantitative coronary angiography software with automated edge detection was used, with the catheter tip serving as the calibration reference. Diameters were measured at three segments of each vessel: the origin, the midlength, and the terminal segment. Tapering was expressed as the percentage reduction in diameter from the proximal to the distal end of the vessel. A single operator performed triplicate measurements while blinded to patient sex, and reliability testing on a random sample of 30 angiograms produced intraclass correlation coefficients above 0.85 for all segments.

The headline findings concern sex differences in the LAD. Females had longer LAD arteries than males, measuring 90.97 ± 25.62 mm compared with 76.6 ± 27.3 mm, a difference that was statistically significant. Females also showed greater overall LAD tapering, at 50.1 ± 20.1 percent versus 46.5 ± 18.2 percent in males, with a significant difference in overall tapering percentage. The correlation between LAD diameter and length was stronger in females, with a correlation coefficient of 0.54 compared with 0.38 in males, and this difference was also statistically significant. The LAD was longer than the LCX in the cohort overall, at 85.1 ± 27.2 mm versus 67.3 ± 21.6 mm, and females had a wider proximal LAD diameter than males.

Not every measured parameter differed by sex. The mean diameter of the left main coronary artery, at 3.8 ± 0.5 mm, did not differ between males and females. Sex differences in the LCX were more limited: there was no significant difference in LCX diameter at the origin or midlength, and at the terminal part of the LCX males actually had a significantly larger diameter than females. The authors characterized these patterns as vessel- and location-specific rather than uniform across the branches of the left main coronary artery, and no significant sex difference was found when comparing average vessel diameters across the LCX and LAD as a whole.

Age emerged as an important consideration in interpreting the results. The women in the cohort were significantly older than the men, averaging 59.3 ± 7.2 years versus 49.6 ± 7.6 years, a gap of roughly a decade that the authors explicitly acknowledge as a potential confounder. To address this, the team constructed multivariable regression models adjusting for both age and body surface area. After adjustment, sex remained independently associated with LAD length, with an unstandardized coefficient of 12.4 mm, and with overall LAD tapering percentage, with a coefficient of 3.8 percent. No significant age-by-sex interaction was observed for LAD length. Separately, the LCX origin diameter showed a significant inverse association with age, while the LAD showed no significant age-related association.

The study also documented patterns that may matter for how coronary anatomy is interpreted across populations. Overall vessel diameters in the Sudanese cohort were numerically smaller than values commonly reported in European, Asian, and North American populations, although the authors note that no direct statistical comparison with another cohort was performed, so these comparisons should be read cautiously. In the cohort, 78 percent of LAD mid-segment diameters were below 2.5 mm, and vessels smaller than 2.75 mm were observed in 62 percent of the women. The authors stress that these observations should not be interpreted as redefining small-vessel disease thresholds or establishing new clinical criteria, since the study did not evaluate procedural or clinical outcomes.

On tapering specifically, the authors are careful to note that progressive arterial tapering of the LAD and LCX is an expected and well-documented anatomical feature, so the study does not claim to demonstrate tapering itself; rather, it quantifies sex- and population-specific tapering patterns in an underrepresented cohort. Compared with published values from a United States cohort, in which LAD tapering was approximately 37.2 percent, both Sudanese males and females in this study showed higher tapering percentages, though the authors caution that cross-study comparisons are limited by differences in measurement methodology. The sex difference in overall tapering, while statistically significant, was modest in absolute terms, at roughly 3.6 percentage points, and its clinical relevance remains unknown.

The authors frame the entire study as descriptive and hypothesis-generating rather than practice-changing. Because the analysis was retrospective and cross-sectional, it cannot establish causal relationships, and the inclusion only of patients with non-obstructive disease means the findings may not generalize directly to patients with obstructive coronary disease or those undergoing intervention. The study did not assess procedural outcomes, restenosis, or hemodynamic parameters, so all interventional implications discussed remain speculative. Data on cardiovascular risk factors, hormonal status including menopausal status, and left ventricular mass were not available, which limits interpretation of the observed anatomical differences. Angiographic measurements are also inherently projection-dependent, and the use of non-standardized angulations across centers may have introduced variability, despite the use of validated quantitative software and blinded measurement.

Within those limits, the authors argue that the findings underscore the value of population- and sex-specific anatomical benchmarks and point toward future prospective, multi-ethnic studies that incorporate advanced imaging, cardiovascular risk factor data, and clinical outcomes. The study’s contribution lies in adding morphometric data from a Sudanese cohort to a literature dominated by European and North American studies, and in highlighting that sex-related differences in coronary geometry, including LAD length and tapering, persist after adjustment for age and body size. Whether these anatomical observations translate into meaningful differences in procedural planning or clinical outcomes in Sudanese patients remains a question for outcome-based research that has not yet been conducted.

Subject of Research: Sex-specific morphometric differences in left coronary artery dimensions and tapering among Sudanese patients with non-obstructive coronary artery disease

Article Title: Sex-Specific Differences in Coronary Artery Dimensions and Tapering: A Sudanese Angiographic Study

Article References: Alhassen, M. M. F., Rezigalla, A. A., Araquib, A. K., Alsharif, M. H. K., Alqarni, A. A., Ali, A. M., Abdelmahmoud, N. Y. E., Ibrahim, E. K., Abdalla, A., Ahmed, N. A. A. M., Awadlseid, K. M. F., Sonpol, H. M. A., Karadawi, N. E., Ahmed, N. E. E., Ali, M. S. B., Abdelaati, A. O. Y., Adam, M. I. E., & Ali, T. O. (2026). Sex-Specific Differences in Coronary Artery Dimensions and Tapering: A Sudanese Angiographic Study. Artery Research, 32(1), Article 41. https://doi.org/10.1007/s44200-026-00138-7

Image Credits: AI Generated

DOI: 10.1007/s44200-026-00138-7

Keywords: coronary artery morphometry, Sudan, angiography, left anterior descending artery, left circumflex artery, tapering, sex differences, non-obstructive coronary artery disease, quantitative coronary angiography, body surface area, retrospective study, cardiac anatomy