Background: Previous studies describing genetics evaluation in spontaneous coronary artery dissection (SCAD) have been retrospective in nature or presented as single case reports. As part of a dedicated clinical program, we evaluated patients in cardiovascular genetics clinic to determine the role of genetically triggered vascular disease and genetic testing in SCAD. Methods and Results: Patient data were entered prospectively into the Massachusetts General Hospital SCAD registry database from July 2013 to September 2017. Clinically indicated genetic testing was conducted based on patient imaging, family history, physical examination, and patient preference. Of the 107 patients enrolled in the registry, 73 underwent cardiovascular genetics evaluation at our center (average age, 45.3±9.4 years; 85.3% female), and genetic testing was performed for 44 patients. A family history of aneurysm or dissection was not a prevalent feature in the study population, and only 1 patient had a family history of SCAD. Six patients (8.2%) had identifiable genetically triggered vascular disease: 3 with vascular Ehlers–Danlos syndrome ( COL3A1 ), 1 with Nail–patella syndrome ( LMX1B ), 1 with autosomal dominant polycystic kidney disease ( PKD1 ), and 1 with Loeys–Dietz syndrome ( SMAD3 ). None of these 6 had radiographic evidence of fibromuscular dysplasia. Conclusions: In this series, 8.2% of the SCAD patients evaluated had a molecularly identifiable disorder associated with vascular disease. The most common diagnosis was vascular Ehlers–Danlos syndrome. Patients with positive gene testing were significantly younger at the time of their first SCAD event. A low threshold for genetic testing should be considered in patients with SCAD.

Despite the paucity of evidence, it is often presumed, and is physiologically plausible, that sudden, acute elevations in blood pressure may transiently increase the risk of recurrent aortic dissection (AD) or rupture in patients with a prior AD, because a post‐dissection aorta is almost invariably dilated and may thus experience greater associated wall stress as compared with a nondilated aorta. Few data are available regarding the specific types and intensities of exercise that may be both safe and beneficial for this escalating patient population. The purpose of this editorial/commentary is to further explore this conundrum for clinicians caring for and counseling AD survivors. Moderate‐intensity cardiovascular activity may be cardioprotective in this patient cohort. It is likely that severe physical activity restrictions may reduce functional capacity and quality of life in post‐AD patients and thus be harmful, underscoring the importance of further exploring the role of physical activity and/or structured exercise in this at‐risk patient population.

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PURPOSE. The current approach to the prevention of diabetic retinopathy relies on intensive anti-diabetes treatment and is only partially successful. A marker of retinopathy risk would enable strategies of surveillance, screening of adjunct drugs, and targeted drug interventions. The authors sought to identify early abnormalities of retinal vessels that are not prevented by the current therapeutic approach. METHODS. Retinal thickness (an informer of vascular permeability) and hemodynamic parameters at baseline and longitudinally were measured in 27 subjects (age, 32 Ϯ 9 years [mean Ϯ SD]) with well-controlled type 1 diabetes of 12.4 Ϯ 6.4 years' duration and no retinopathy, and in 27 control subjects. In a subset of 17 patients and 11 controls, the hemodynamic response to reclining, a postural change that increases retinal perfusion pressure, was measured. RESULTS. Baseline foveal thickness and hemodynamic parameters were similar in the diabetic and control subjects. Foveal thickness increased over 12 months in the diabetic subjects, from 217 Ϯ 22 m to 222 Ϯ 20 m (P ϭ 0.0036), remaining however within the normal range. Reclining uncovered in 47% of diabetic subjects (P ϭ 0.016 compared with controls) an absent myogenic response (i.e., unchanged or increased arterial diameter instead of the normal decrease). The patterns were repeatable. Only the diabetic group with defective vasoconstriction showed widening arterial diameter over 12 months, a change presaging vascular dilatation in diabetic retinopathy. CONCLUSIONS. Defective myogenic response to pressure was the first detectable abnormality of retinal vessels in subjects with well-controlled type 1 diabetes. Because of its selective occurrence, interpretability in individual patients, and pathogenic potential, the abnormality deserves evaluation as a risk marker for retinopathy. (

Aims/hypothesis Abnormalities in retinal haemodynamics have been reported in patients with type 1 diabetes in advance of clinical retinopathy. These abnormalities could therefore be useful as early markers or surrogate endpoints for studying the microangiopathy. Since the DCCT, the increased focus on good glycaemic control is changing the natural history of diabetic retinopathy. Based on this, the aim of this study was to investigate whether patients with type 1 diabetes treated entirely or mostly in the post-DCCT era and tested in the absence of confounding factors show retinal haemodynamic abnormalities. Methods We measured retinal haemodynamics by laser Doppler flowmetry in 33 type 1 diabetic individuals with no or minimal retinopathy (age 30±7 years, duration of diabetes 8.8±4.6 years, 9% showing microaneurysms), and 31 age-and sex-matched non-diabetic controls. The study participants were not taking vasoactive medications, and blood glucose at the time of haemodynamic measurements was required to be between 3.8 and 11.1 mmol/l. Results HbA 1c was 7.5±1.2% and blood glucose 7.7± 2.8 mmol/l in these type 1 diabetic individuals, indicating relatively good glycaemic control. Retinal blood speed, arterial diameter and blood flow were not different between the diabetic individuals and the matched controls. Conclusions/interpretation Type 1 diabetic patients with no or minimal retinopathy who maintain relatively good glycaemic control do not show abnormalities of the retinal circulation at steady state, even after several years of diabetes. In such patients it may be necessary to test the vascular response to challenges to uncover any subtle abnormalities of the retinal vessels.