Myocardial Bridging Unmasks as an Acute Coronary Syndrome from Dehydration

A 50-year-old male presented for loss of consciousness. He was initially treated with intravenous epinephrine and fluids, and an electrocardiogram (ECG) displayed an ST-segment elevation in lead aVR with global ST-segment depressions. A subsequent left heart catheterization revealed that the middle segment of the left anterior descending artery (LAD) demonstrated severe stenosis during systole but would become patent during diastole, which was suggestive of myocardial bridging. After stopping the epinephrine and increasing the fluid infusion, the ECG changes rapidly resolved. The patient had later admitted to significant dehydration all day. Myocardial bridging is a congenital anomaly in which a coronary artery segment courses through the myocardium instead of the usual epicardial surface. Occasionally, myocardial bridging may present similarly to acute coronary syndrome in severe dehydration or hyperadrenergic states. The diagnosis can be made through coronary angiography, which reveals a dynamic vessel obstruction pattern corresponding with the cardiac cycle. Long-term effects may also include accelerated atherosclerosis. Treatment consists of reversing precipitating causes during acute presentations and decreasing the risk of coronary artery disease on a chronic basis.

Prevalence of pathological FFRCT values without coronary artery stenosis in an asymptomatic marathon runner cohort

Objectives To evaluate computed tomography fractional flow reserve (FFRCT) values in distal parts of the coronaries in an asymptomatic cohort of marathon runners without any coronary stenosis for potentially false-positive values. Methods Ninety-eight asymptomatic male marathon runners (age 53 ± 7 years) were enrolled in a prospective monocentric study and underwent coronary computed tomography angiography (CCTA). CCTA data were analyzed for visual coronary artery stenosis. FFRCT was evaluated in 59 participants without coronary artery stenosis in proximal, mid, and distal coronary sections using an on-site software prototype. Results In participants without coronary artery stenosis, abnormal FFRCT values ≤ 0.8 in distal segments were found in 22 participants (37%); in 19 participants in the LAD; in 5 participants in the LCX; and in 4 participants in the RCA. Vessel diameters in participants with FFRCT values > 0.80 compared to ≤ 0.80 were 1.6 ± 0.3 mm versus 1.5 ± 0.3 mm for distal LAD (p = 0.025), 1.8 ± 0.3 mm versus 1.6 ± 0.5 mm for distal LCX (p = 0.183), and 2.0 ± 0.4 mm versus 1.5 ± 0.2 mm for distal RCA (p < 0.001). Conclusions Abnormal FFRCT values of ≤ 0.8 frequently occurred in distal coronary segments in subjects without any anatomical coronary artery stenosis. This effect is only to some degree explainable by small distal vessel diameters. Therefore, the validity of hemodynamic relevance evaluation using FFRCT in distal coronary artery segment stenosis is reduced. Key Points • Abnormal FFRCT values (≤ 0.8) occurred in over a third of the subjects in the distal LAD despite the absence of coronary artery stenosis.. • Therefore, the validity of hemodynamic relevance evaluation in distal coronary artery segment stenosis is reduced. • Decision-making based on abnormal FFRCT values in distal vessel sections should be performed with caution and only in combination with visual assessment of the grade of stenosis..

The comparison of serum TGF-beta levels and associated polymorphisms in patients with coronary artery ectasia and normal coronary artery

Background Coronary artery ectasia (CAE) is described as the enlargement of a coronary artery segment by 1.5 times or more, which is generally associated with the atherosclerotic process. Atherosclerotic changes lead to arterial remodeling result in CAE. In our study, we measured serum transforming growth factor (TGF)-β1 levels, which have a protective role against atherosclerosis. Further, we aimed to assess the TGF-β1 gene variants rs1800469 (–509C>T, c.−1347C>T) and rs1800470 (c.+29T>C, p.Pro10Leu, rs1982073), which might have an effect on TGF production. Overall, 2877 patients were screened including 56 patients with CAE and 44 patients with normal coronary arteries who were included in the study. Serum TGF-β1 levels were measured using ELISA and compared between two groups. Additionally, TGF-β1 rs1800469 and rs1800470 gene variations were determined using TaqMan® SNP Genotyping Assays. Results Serum TGF-β1 levels were significantly lower in patients with CAE than in controls (p=0.012). However, there was no difference in terms of the genotype and allele distributions of TGF-β1 rs1800469 and rs1800470 polymorphisms. Serum TGF-β1 levels were higher in individuals carrying the TGF-β1 rs1800470 G allele (GG+AG) than in individuals with normal homozygous AA genotype in the CAE group (p=0.012). Conclusion Our findings suggest that lower serum TGF-β1 levels are associated with an increased risk for CAE development and that TGF-β1 polymorphisms exert a protective effect. Furthermore, TGF-β1 rs1800470 G allele carriers were shown to have higher TGF-β1 levels in the CAE group. This suggests that having the G allele in the TGF-β1 rs1800470 polymorphism could prevent CAE development.

‘A bridge over troubled water’: a case report

Background Myocardial bridge (MB) is the most common inborn coronary artery variant, in which a portion of myocardium overlies a major epicardial coronary artery segment. Myocardial bridge has been for long considered a benign condition, although it has been shown to cause effort-related ischaemia. Case summary We present the case of a 17-year-old female patient experiencing chest pain during physical activity. Since her symptoms became unbearable, electrocardiogram and echocardiography were performed together with a coronary computed tomography scan, revealing an MB on proximal-mid left anterior descending artery. In order to unequivocally unmask the ischaemic burden lent by MB, the patient underwent coronary angiography and physiological invasive test: instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR) were calculated, both at baseline and after dobutamine infusion (5 µg/kg/min). At baseline, iFR value was borderline (= 0.89), whereas after dobutamine infusion and increase in the heart rate, the patient suffered chest pain. This symptom was associated with a decrease in the iFR value up to 0.77. Consistently, when FFR was performed, a value of 0.92 was observed at baseline, while after inotrope infusion the FFR reached the haemodynamic significance (= 0.79). Therefore, a medical treatment with bisoprolol was started. Discussion Our clinical case shows the importance of a comprehensive non-invasive and invasive assessment of MB in young patients experiencing chest pain, with significant limitation in the daily life. The coronary functional indexes allow to detect the presence of MB-derived ischaemia, thus guiding the decision to undertake a medical/surgical therapy.

Image quality of automatic coronary CT angiography reconstruction for patients with HR ≥ 75 bpm using an AI-assisted 16-cm z-coverage CT scanner

Background Coronary CT angiography (CCTA) is a complicated CT exam in comparison to other CT protocols. Exam success highly depends on image assessment of experienced radiologist and the procedure is often time-consuming. This study aims to evaluate feasibility of automatic CCTA reconstruction in 0.25 s rotation time, 16 cm coverage CT scanner with best phase selection and AI-assisted motion correction. Methods CCTA exams of 90 patients with heart rates higher than 75 bpm were included in this study. Two image series were reconstructed—one at automatically selected phase and another with additional motion correction. All reconstructions were performed without manual interaction of radiologist. A four-point Likert scale rating system was used to evaluate the image quality of coronary artery segment by two experienced radiologists, according to the 18-segment model. Analysis was done on per-segment basis. Results Total 1194 out of the 1620 segments were identified for quality evaluation in 90 patients. After automatic best phase selection, 1172 segments (98.3%) were rated as having diagnostic image quality (scores 2–4) and the average score is 3.64 ± 0.55. When motion corrections were applied, diagnostic segment number increases to 1192 (99.8%) and the average score is 3.85 ± 0.37. Conclusions With the help of 0.25 s rotation speed, 16-cm z-coverage and AI-assisted motion correction algorithm, CCTA exam reconstruction could be performed with minimum radiologist involvement and still meet image quality requirement.

Coronary arterial abnormalities detected in children over 10 years following initial Kawasaki disease using cardiac computed tomography

Objective: To evaluate whether Kawasaki disease predisposes to premature atherosclerosis and to assess status of coronary artery abnormalities at least 10 years after diagnosis. Material and methods: A prospective study was carried out on 21 patients who were diagnosed with Kawasaki disease at least 10 years back and are on regular follow-up. The study was conducted on 128 Slice Dual Source computed tomography scanner with electrocardiography-triggered radiation optimised protocols for assessment of coronary artery abnormalities and calcifications. Results: Study cohort had 21 subjects – 15 males and 6 females (age range: 11–23 years; mean: 15.76 + 3.72 years). Mean age at time of diagnosis was 3.21 + 2.48 years. Mean time interval from diagnosis of Kawasaki disease to computed tomography coronary angiography was 12.59 + 2.89 years. Four children had evidence of coronary artery abnormalities on transthoracic echocardiography at time of diagnosis. Of these, two had persistent abnormalities on computed tomography coronary angiography. One subject (4.76%) had coronary calcification that was localised to abnormal coronary artery segment. Four coronary artery abnormalities (one saccular; three fusiform aneurysms) were noted in two subjects. Conclusion: Prevalence of coronary artery calcification is low and, if present, is localised to abnormal segments. This calcification is likely dystrophic rather than atherosclerotic. It appears that coronary artery abnormalities can persist for several years after acute episode of Kawasaki disease. Periodic follow-up by computed tomography coronary angiography is now a feasible non-invasive imaging modality for long term surveillance of patients with Kawasaki disease who had coronary artery abnormalities at time of diagnosis.

Congenital atresia of the left main coronary artery: management of a 5-year-old child in extremis

Atresia of the left main coronary artery is a rare coronary anomaly. We describe the case of a 5-year-old child presenting in emergency in extremis. Clinical findings of haemodynamic collapse, malignant ventricular tachyarrhythmias and severe mitral regurgitation were indicative of a possible ischaemic aetiology. Surgical revascularization of the atretic left main coronary artery segment using an interposition autologous saphenous vein graft was successfully performed.

Anomalous aortic origin of coronary arteries: is the unroofing procedure always appropriate?

OBJECTIVES Anomalous aortic origin of the coronary artery (AAOCA) with an interarterial ± an intramural course is a rare anomaly that carries a high risk of ischaemic events and even sudden death. The unroofing of the intramural course has been adopted as the gold standard surgical treatment. However, some anatomical forms need alternative techniques. METHODS We reviewed the surgical cohort with AAOCA managed at our institution between 2005 and 2019 and analysed the anatomical and clinical outcomes. RESULTS Thirty-nine patients underwent surgical interventions. The median age was 14 years (10–26 years). Twenty-eight patients (72%) had right AAOCA, and 11 (28%) had left AAOCA. Thirty-one (80%) patients presented with symptoms. The symptoms were chest pain in 22 patients (56%), syncope in 5 patients (13%), cardiac arrest during exercise in 2 patients (5%), dyspnoea in 6 patients (15%) and dizziness in 13 patients (33%). An ischaemic test was performed in 32 patients: Only 4 patients (10%) had positive results from the ischaemic test. All patients had computed tomography angiography scans to confirm the precise anatomical features of the anomaly. Repair techniques included 30 unroofing procedures (77%) with an associated translocation of the pulmonary artery for 11 patients in our early experience. In 6 patients the unroofing procedure was not feasible because of the absence of an intramural distinct segment or was judged intraoperatively not appropriate. A reimplantation of the anomalous coronary artery was performed in 2 patients (5%); 3 patients had coronary artery bypass grafting procedures (7%); and 3 (8%) had an isolated translocation of the pulmonary artery. There were no early or late deaths. All patients were free of symptoms. Computed tomography angiography scans performed in 31 cases showed a patent, non-restrictive coronary artery ostium. Seventeen patients underwent postoperative ischaemia testing and showed no evidence of ischaemia. CONCLUSIONS Surgical correction in AAOCA is mandatory both for symptomatic and for asymptomatic patients with evidence of myocardial ischaemia under stress or with a restricted coronary artery segment. Surgical unroofing remains the gold standard but is not appropriate for all forms: alternative techniques should be considered. Surgical results are promising.

Management of Coronary Artery Aneurysm – Report of two cases

Coronary artery aneurysm (CAA) is described as a localized dilatation of a coronary artery segment by more than 1.5-fold compared with the adjacent normal segments. The incidence of CAA varies from 0.3 to 5.3% with atherosclerosis, Takayasu arteritis, congenital disorders, Kawasaki disease, and percutaneous coronary intervention (PCI) being the common etiologic factors. Owing to its varying presentation and absence of robust treatment guidelines, management of CAA is a challenge. Management of every patient must be tailored according to the presentation and expertise of the cardiac team available. Here, we present case reports of two patients with CAA who presented with acute coronary syndrome. As a result of unstable presentation, both patients underwent immediate intervention (CABG and PCI respectively) with successful revascularization having no complication and mortality.

P2647Impact of hypertension on extent of non-obstructive coronary artery disease (The NORIC registry)

Background In non-obstructive coronary artery disease (CAD), increasing extent of disease is associated with a worse prognosis. Statin therapy has been suggested to improve the prognosis. Whether hypertension, a modifiable CV risk factor, affects the extent of non-obstructive CAD in patients with stable angina is less explored. Purpose To assess the association between hypertension and extent of non-obstructive coronary artery disease. Methods We identified 1117 patients (mean age 62±10 years, 48% women) from the Norwegian Registry for Invasive Coronary angiography (NORIC). All subjects had stable angina and non-obstructive CAD defined as 1–49% stenosis in any coronary artery segment by coronary computed tomography angiography (CCTA). The extent of non-obstructive CAD was assessed as coronary artery segment involvement score (SIS) on CCTA. Extensive non-obstructive CAD was defined as SIS≥4. Results Hypertension was present in 44% and patients with hypertension were older with a higher prevalence of diabetes, obesity, smoking and statin therapy (all p<0.05). Coronary artery SIS and calcium score were higher in patients with hypertension compared to those without hypertension, (3.1±2.0 vs. 2.6±1.7, p<0.001 and 41 (116) vs. 32 (91) HU, p<0.05), respectively. There was no significant sex difference in the prevalence of hypertension. In univariable analysis, hypertension, age, calcium score and statin treatment were significantly associated with extensive non-obstructive CAD (Table). Hypertension remained a strong, independent predictor of extensive non-obstructive CAD after adjusting for other known covariables (Table). Table 1. Covariables of extensive non-obstructive CAD in univariable and multivariable logistic regression analysis Univariable analysis Multivariable analysis OR 95% CI p-value OR 95% CI p-value Hypertension 1.57 1.21–2.04 0.001 1.47 1.03–2.10 0.035 Age 1.06 1.05–1.08 <0.001 1.04 1.01–1.06 0.001 Calcium score 1.02 1.01–1.02 <0.001 1.01 1.01–1.02 <0.001 Statin treatment 1.34 1.03–1.75 0.029 1.20 0.83–1.70 0.341 Smoking 1.33 1.00–1.77 0.052 1.24 0.86–1.78 0.251 Diabetes mellitus 1.34 0.86–2.12 0.191 1.10 0.57–2.09 0.781 Obesity 1.03 0.76–1.41 0.839 1.19 0.79–1.80 0.425 Conclusions Hypertension is associated with extensive non-obstructive CAD in patients with stable angina, suggesting that early and aggressive antihypertensive treatment may impact disease progression.