Coronary sinus reducer for the treatment of refractory angina (ORBITA-COSMIC): a randomised, placebo-controlled trial

BACKGROUND

The coronary sinus reducer (CSR) is proposed to reduce angina in patients with stable coronary artery disease by improving myocardial perfusion. We aimed to measure its efficacy, compared with placebo, on myocardial ischaemia reduction and symptom improvement.

METHODS

ORBITA-COSMIC was a double-blind, randomised, placebo-controlled trial conducted at six UK hospitals. Patients aged 18 years or older with angina, stable coronary artery disease, ischaemia, and no further options for treatment were eligible. All patients completed a quantitative adenosine-stress perfusion cardiac magnetic resonance scan, symptom and quality-of-life questionnaires, and a treadmill exercise test before entering a 2-week symptom assessment phase, in which patients reported their angina symptoms using a smartphone application (ORBITA-app). Patients were randomly assigned (1:1) to receive either CSR or placebo. Both participants and investigators were masked to study assignment. After the CSR implantation or placebo procedure, patients entered a 6-month blinded follow-up phase in which they reported their daily symptoms in the ORBITA-app. At 6 months, all assessments were repeated. The primary outcome was myocardial blood flow in segments designated ischaemic at enrolment during the adenosine-stress perfusion cardiac magnetic resonance scan. The primary symptom outcome was the number of daily angina episodes. Analysis was done by intention-to-treat and followed Bayesian methodology. The study is registered with ClinicalTrials.gov, NCT04892537, and completed.

FINDINGS

Between May 26, 2021, and June 28, 2023, 61 patients were enrolled, of whom 51 (44 [86%] male; seven [14%] female) were randomly assigned to either the CSR group (n=25) or the placebo group (n=26). Of these, 50 patients were included in the intention-to-treat analysis (24 in the CSR group and 26 in the placebo group). 454 (57%) of 800 imaged cardiac segments were ischaemic at enrolment, with a median stress myocardial blood flow of 1·08 mL/min per g (IQR 0·77-1·41). Myocardial blood flow in ischaemic segments did not improve with CSR compared with placebo (difference 0·06 mL/min per g [95% CrI -0·09 to 0·20]; Pr(Benefit)=78·8%). The number of daily angina episodes was reduced with CSR compared with placebo (OR 1·40 [95% CrI 1·08 to 1·83]; Pr(Benefit)=99·4%). There were two CSR embolisation events in the CSR group, and no acute coronary syndrome events or deaths in either group.

INTERPRETATION

ORBITA-COSMIC found no evidence that the CSR improved transmural myocardial perfusion, but the CSR did improve angina compared with placebo. These findings provide evidence for the use of CSR as a further antianginal option for patients with stable coronary artery disease.

FUNDING

Medical Research Council, Imperial College Healthcare Charity, National Institute for Health and Care Research Imperial Biomedical Research Centre, St Mary's Coronary Flow Trust, British Heart Foundation.

Surgical management of multiple coronary artery to coronary sinus fistulas with giant left circumflex artery and multivalvular infective endocarditis

Coronary artery fistula (CAF) is characterized as a congenital or acquired abnormal communication between a coronary artery and any of the four chambers of the heart (coronary-cameral fistula) or great vessels (coronary arteriovenous fistula) bypassing the capillaries within myocardium. CAF is a rare disease, challenging to diagnose and treat depending on the anatomical location and type of the fistula and accompanying diseases. This study aims to report a case with multiple coronary artery to coronary sinus (CS) fistulas with giant left circumflex artery and multivalvular infective endocarditis.

A rare case of isolated persistent left superior vena cava diagnosed by echocardiography

BACKGROUND

The persistent left superior vena cava (PLSVC) is an infrequent vascular variant. PLSVC with absent right superior vena cava, also known as isolated PLSVC, is an exceptionally rare entity. In this case we present a patient with isolated PLSVC draining to coronary sinus, diagnosed incidentally during echocardiography.

CASE PRESENTATION

A 35-year-old man underwent a transthoracic echocardiography which showed an enormously dilated coronary sinus. Hand-agitated saline was injected via peripheral intravenous cannulas. The contrast appeared firstly in the coronary sinus before it opacified the right atrium. Since this was also visible by the right antecubital saline injection, it indicated an extremely rare case of PLSVC with the absence of right superior vena cava which was confirmed by cardiac magnetic resonance.

CONCLUSIONS

The finding of a distinctively dilated coronary sinus in echocardiography led us to further investigation using agitated saline that revealed an infrequent anomaly termed isolated PLSVC. The in-depth diagnosis of this vascular variant is crucial considering that it may lead to important clinical implications, such as difficulties with central venous access, especially in the current era of a rapid development of cardiac device therapies.

Ablation of epicardial ventricular focus through coronary sinus using pulsed-field ablation. A case report

INTRODUCTION

With the entry of pulsed-field ablation (PFA) into electrophysiology, new possibilities for ablation of different substrates such as epicardial foci of premature ventricular contractions (PVCs) from coronary venous system (CVS) have been opened.

METHODS

This article focuses on a case of a 27-year-old patient with frequent monomorphic PVCs of epicardial origin, treated by radiofrequency ablation, followed by PFA.

RESULTS

After unsuccessful focus ablation through CVS with RFA, successful ablations from the same region with PFA were achieved.

CONCLUSION

This is the first described case of successful ablation of epicardial PVCs using PFA, which we hope will help in defining indications for this novel technology and enhance quality of treatment for patients with different arrhythmias.

Pressure-Controlled Intermittent Coronary Sinus Occlusion (PiCSO) in Acute Myocardial Infarction: The PiCSO-AMI-I Trial

BACKGROUND

Primary percutaneous coronary intervention (pPCI) has improved clinical outcomes in patients with ST-segment-elevation myocardial infarction. However, as many as 50% of patients still have suboptimal myocardial reperfusion and experience extensive myocardial necrosis. The PiCSO-AMI-I trial (Pressure-Controlled Intermittent Coronary Sinus Occlusion-Acute Myocardial Infarction-I) evaluated whether PiCSO therapy can further reduce myocardial infarct size (IS) in patients undergoing pPCI.

METHODS

Patients with anterior ST-segment-elevation myocardial infarction and Thrombolysis in Myocardial Infarction flow 0-1 were randomized at 16 European centers to PiCSO-assisted pPCI or conventional pPCI. The PiCSO Impulse Catheter (8Fr balloon-tipped catheter) was inserted via femoral venous access after antegrade flow restoration of the culprit vessel and before proceeding with stenting. The primary end point was the difference in IS (expressed as a percentage of left ventricular mass) at 5 days by cardiac magnetic resonance. Secondary end points were the extent of microvascular obstruction and intramyocardial hemorrhage at 5 days and IS at 6 months.

RESULTS

Among 145 randomized patients, 72 received PiCSO-assisted pPCI and 73 conventional pPCI. No differences were observed in IS at 5 days (27.2%±12.4% versus 28.3%±11.45%; P=0.59) and 6 months (19.2%±10.1% versus 18.8%±7.7%; P=0.83), nor were differences between PiCSO-treated and control patients noted in terms of the occurrence of microvascular obstruction (67.2% versus 64.6%; P=0.85) or intramyocardial hemorrhage (55.7% versus 60%; P=0.72). The study was prematurely discontinued by the sponsor with no further clinical follow-up beyond 6 months. However, up to 6 months of PiCSO use appeared safe with no device-related adverse events.

CONCLUSIONS

In this prematurely discontinued randomized trial, PiCSO therapy as an adjunct to pPCI did not reduce IS when compared with conventional pPCI in patients with anterior ST-segment-elevation myocardial infarction. PiCSO use was associated with increased procedural time and contrast but no increase in adverse events up to 6 months.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03625869.

Myocardial Blood Flow Determination From Contrast-Free Magnetic Resonance Imaging Quantification of Coronary Sinus Flow

BACKGROUND

Determination of myocardial blood flow (MBF) with MRI is usually performed with dynamic contrast enhanced imaging (MBFDCE ). MBF can also be determined from coronary sinus blood flow (MBFCS ), which has the advantage of being a noncontrast technique. However, comparative studies of MBFDCE and MBFCS in large cohorts are lacking.

PURPOSE

To compare MBFCS and MBFDCE in a large cohort.

STUDY TYPE

Prospective, sequence-comparison study.

POPULATION

147 patients with type 2 diabetes mellitus (age: 56+/-12 years; 106 male; diabetes duration: 12.9+/-8.1 years), and 25 age-matched controls.

FIELD STRENGTH/SEQUENCES

1.5 Tesla scanner. Saturation recovery sequence for MBFDCE vs. phase-contrast gradient-echo pulse sequence (free-breathing) for MBFCS .

ASSESSMENT

MBFDCE and MBFCS were determined at rest and during coronary dilatation achieved by administration of adenosine at 140 μg/kg/min. Myocardial perfusion reserve (MPR) was calculated as the stress/rest ratio of MBF values. Coronary sinus flow was determined twice in the same imaging session for repeatability assessment.

STATISTICAL TESTS

Agreement between MBFDCE and MBFCS was assessed with Bland and Altman's technique. Repeatability was determined from single-rater random intraclass and repeatability coefficients.

RESULTS

Rest and stress flows, including both MBFDCE and MBFCS values, ranged from 33 to 146 mL/min/100 g and 92 to 501 mL/min/100 g, respectively. Intraclass and repeatability coefficients for MBFCS were 0.95 (CI 0.90; 0.95) and 5 mL/min/100 g. In Bland-Altman analysis, mean bias at rest was -1.1 mL/min/100 g (CI -3.1; 0.9) with limits of agreement of -27 and 24.8 mL/min/100 g. Mean bias at stress was 6.3 mL/min/100 g (CI -1.1; 14.1) with limits of agreement of -86.9 and 99.9. Mean bias of MPR was 0.11 (CI: -0.02; 0.23) with limits of agreement of -1.43 and 1.64.

CONCLUSION

MBF may be determined from coronary sinus blood flow, with acceptable bias, but relatively large limits of agreement, against the reference of MBFDCE .

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY STAGE: 2.

Giant coronary sinus aneurysm: an incidental discovery in a case of acute coronary syndrome

Coronary sinus (CS) anomalies, although infrequent, are increasingly diagnosed with advances in interventional procedures and imaging techniques. Most cases are asymptomatic and incidentally diagnosed. We present a case of an elderly male without comorbidities who presented with acute angina. Coronary catheterisation revealed a double-vessel disease, but incidentally, sequential angiograms captured contrast filling in the levophase of CS, revealing a giant CS. Primary percutaneous angioplasty of the right coronary artery was performed successfully. Echocardiography confirmed the aneurysm, and a CT scan showed an aneurysmally dilated CS and other coronary veins alongside a normal-sized persistent left superior vena cava draining to the right atrium through CS. CS aneurysms may lead to complications such as thrombosis, embolic events, arrhythmias and heart failure, stressing the importance of vigilant monitoring and timely intervention. This case underscores the significance of recognising CS anomalies in cardiac procedures, even when asymptomatic, for proper management.

Snare technique failure in extracting an embolized coronary sinus reducer to the pulmonary artery

We report the case of a 79-year-old male patient who benefited from the implantation of a coronary sinus reducer (CSR) (Reducer; Neovasc, Inc.) in the management of typical angina with mild exertion with optimal medical treatment.

The effectiveness and safety of temporary transvenous cardiac pacing leads placement into coronary sinus vein in patients with sick sinus syndrome

BACKGROUND

The temporary pacing lead routinely is placed into right ventricular (RV), which pose a risk of dislocation and cardiac perforation.

OBJECTIVE

We aim to evaluate the effectiveness and safety of temporary transvenous cardiac pacing (TTCP) leads placement into the coronary sinus vein (CSV) in patients with sick sinus syndrome (SSS).

METHODS

We investigated patients with SSS who underwent TTCP lead placement into the CSV under the guidance of X-ray between January 2013 and May 2023. Patients were randomly divided into two groups: RV group (n = 33) and CSV group (n = 22). The ordinary passive bipolar electrodes were applied in both groups. In RV groups, electrodes were placed into RV. In CSV group, electrodes were placed into CSV. We evaluated the operation duration, fluoroscopic exposure, first-attempt success rate of leads placement, pacing threshold, success rate of leads placement, rate of leads displacement, and complications.

RESULTS

Compared with that in RV group, the procedure time, fluoroscopic exposure was significantly prolonged, while the first-attempt success rate of lead placement was obviously increased in CSV group (both p < .05). Compared with that in RV group, the rate of leads displacement is lower in CSV group (both p < .05). There were three patients occurred cardiac perforation in RV group, but no cardiac perforation was reported in CSV group (p > .05).

CONCLUSION

TTCP leads placement into the CSV is an effective and safe strategy in patients with SSS. It indicates a high rate of pacing effectiveness with low device replacement and complication rates.

A Surgical Case of Partially Unroofed Coronary Sinus Atrial Septal Defect in an Elderly Patient Diagnosed by Preoperative Contrast-Enhanced Computed Tomography

Unroofed coronary sinus syndrome is a rare congenital cardiac anomaly, involving some anatomical variations. Approximately 60% of patients with unroofed coronary sinus syndrome have a concomitant atrial septal defect, which is termed unroofed coronary sinus atrial septal defect (CSASD). The precise detection of these abnormalities has been usually difficult with conventional echocardiography, mostly due to its small and complex structures. Herein, we report a case with unroofed coronary sinus atrial septal defect, in which preoperative contrast-enhanced computed tomography (CT) was useful in the operative decision making. We successfully repaired the defective roof of the coronary sinus with a bovine patch, while eliminating the inter-atrial shunt. The patient's postoperative course was uneventful with no residual shunt.

Coronary Sinus Narrowing Improves Coronary Microcirculation Function in Patients With Refractory Angina: A Multicenter Prospective INROAD Study

BACKGROUND

The underlying mechanisms responsible for the clinical benefits following coronary sinus narrowing and pressure elevation remain unclear. The present study aims to investigate whether coronary sinus narrowing improves the indexes of coronary microcirculatory function.

METHODS

Patients with refractory angina who had a clinical indication for reducer implantation underwent invasive physiological assessments before and 4 months after the procedure. The primary outcome was the change in the values of the index of microcirculatory resistance. Secondary end points included changes in coronary flow reserve and the resistive resistance ratio values. Angina status was assessed with the Canadian Cardiology Society class and the Seattle Angina Questionnaire.

RESULTS

Twenty-four patients with a history of obstructive coronary artery disease and prior coronary revascularization (surgical and percutaneous) treated with reducer implantation were enrolled, and 21 of them (87%) underwent repeated invasive coronary physiological assessment after 4 months. The index of microcirculatory resistance values decreased from 33.35±19.88 at baseline to 15.42±11.36 at 4-month follow-up (P<0.001; mean difference, -17.90 [95% CI, -26.16 to -9.64]). A significant (≥20% from baseline) reduction of the index of microcirculatory resistance was observed in 15 (71.4% [95% CI, 47.8%-88.7%]) patients. The number of patients with abnormal index of microcirculatory resistance (≥25) decreased from 12 (57%) to 4 (19%; P=0.016). Coronary flow reserve increased from 2.46±1.52 to 4.20±2.52 (mean difference, 1.73 [95% CI, 0.51-2.96]). Similar findings were observed for resistive resistance ratio values. Overall, 16 patients (76.1%) had an improvement of 1 Canadian Cardiology Society class. Seattle Angina Questionnaire summary score increase of around 3 points (3.01 [95% CI, 1.39-4.61]).

CONCLUSIONS

Coronary sinus reduction implantation is associated with a significant improvement in the parameters of coronary microcirculatory function. These findings provide insights into the improvement of angina symptoms and may have implications for the treatment of coronary microvascular dysfunction.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05174572.

Comparison between conventional approach and three-dimensional mapping system in the catheter ablation of accessory pathway associated with coronary sinus diverticulum: A single-center experience

BACKGROUND

Posteroseptal accessory pathways (APs) associated with coronary sinus (CS) diverticulum present a rare and challenge for ablation. This study aimed to compare the safety and efficacy of conventional approach and three-dimensional (3D) mapping system in the catheter ablation.

METHODS AND RESULTS

This was a retrospective study of all patients (from January 2013 to July 2022) who underwent catheter ablation of posteroseptal AP associated with CS diverticula in our center. Patients who underwent catheter ablation using the traditional fluoroscopy method were included in the conventional method group (n = 13). Patients who underwent catheter ablation using the 3D mapping method were included in the 3D mapping group (n = 11). Clinical characteristics, ablation procedure, and outcomes were recorded and analyzed between the two groups. Out of 669 patients with posteroseptal APs, 24 of them (3.6%) were associated with CS diverticula. All patients in both groups successfully completed the electrophysiological study. In the conventional method group, two patients experienced complications (one patient with pericardial effusion and the other patient with femoral arterial hematoma), and two patients had recurrence. However, no patients suffered from complications or recurrence during follow-up. The procedure time and fluoroscopy time in the conventional method group were significantly longer than those in the 3D mapping method group.

CONCLUSIONS

The utilization of 3D mapping led to reduced fluoroscopy time, shorter procedure duration, enhanced acute success rates, and decreased incidence of complications.

Coronary sinus ablations in pediatric patients with supraventricular arrhythmias

BACKGROUND

Intracoronary sinus ablations have been performed for various arrhythmical substrates. The aim of this study is to report our experience on pediatric patients of the safety and efficacy of ablations in the coronary sinus.

METHODS

This is a retrospective study of all patients who underwent ablations in the coronary sinus from October 2013 to October 2021 at a single center. Clinical presentation, type of arrhythmia causing tachycardia, ablation procedure, and outcome were recorded.

RESULTS

A total of 27 patients were included in the study. Nineteen (69%) of those followed up received a diagnosis of Wolff-Parkinson-White syndrome (WPW), 4 (15%) were cases of supraventricular tachycardia with concealed accessory pathway (AP), 2 (8%) were cases of focal atrial tachycardia, and 2 (8%) were cases of permanent junctional reciprocating tachycardia. Negative delta wave was noteworthy especially in lead II in 11/19 (58%) cases and coronary sinus diverticulum was detected in the WPW cases. Of those with manifest AP (19 cases), 15 (79%) had a high-risk AP and the AP in all WPW cases was adenosine unresponsive. Radiofrequency (RF) catheter ablation was performed in 25/27 (93%) cases during the procedure, and 16/25 (64%) of these were irrigated RF catheters. No complications were observed in the follow-up, including coronary artery injury.

CONCLUSIONS

Catheter ablation of supraventricular tachyarrhythmias can be accomplished effectively and potentially safely within the coronary sinus. Coronary sinus diverticula should be suspected in patients with manifest posteroseptal APs who have a previous failed ablation and typical electrocardiographic signs.

Antidromic and orthodromic reciprocating tachycardias over a novel left-sided accessory pathway involving the vein of Marshall and coronary sinus musculature

INTRODUCTION

Herein, we present a rare case of the successful ablation of an accessory pathway (AP) involving the Marshall Bundle (MB) and coronary sinus musculature (CSM) in a 40-year-old man with Wolff-Parkinson-White syndrome.

METHODS AND RESULTS

An orthodromic reciprocating tachycardia (ORT) was inducible with the earliest atrial activation site located at the posterolateral mitral annulus. The local conduction and the cycle length of ORT was prolonged by peri-mitral ablation; however, it failed to block the AP. The atrial insertion of the AP was identified by remapping during ORT at the left atrial ridge, which was away from the mitral annulus, where ablation was successful. Together with the electrophysiological findings in CSM potentials, we conclude that the epicardial MB-CSM connection functioned as the AP in this patient.

CONCLUSION

The novel variant form of AP comprised of MB and CSM should be noted. The atrial insertion of the MB may be the target of catheter ablation.

Keeping it in the family: Use of the grandmother, mother, and child technique to navigate complex anatomy during Coronary sinus Reducer Implantation

The Coronary Sinus Reducer® (CSR) is an emerging therapy for refractory angina recommended once no further pharmacologic or coronary revascularization options are available. We present the case of a 72-year-old man who underwent CSR implantation. Complex coronary sinus anatomy necessitated an innovative "grandmother, mother, and child" catheter approach.

Successful catheter ablation of the accessory pathway in an unusual location in a 13-year-old girl with a coronary sinus diverticulum and Wolff-Parkinson-White syndrome

Wolff-Parkinson-White syndrome is a congenital cardiac pre-excitation syndrome that is effectively treated by ablating the accessory pathway. However, accessory pathways located in the posteroseptal region can sometimes be challenging. In this paper, we present the successful ablation of the epicardial posteroseptal accessory pathway through the middle cardiac vein in a 13-year-old girl with a coronary sinus diverticulum and Wolff-Parkinson-White syndrome, after unsuccessful ablation attempts at different locations. If the ablation procedure fails, the possibility of the posteroseptal pathway should be kept in mind, and coronary sinus angiography should be performed. In cases with a coronary sinus diverticulum where ablation is not successful, other coronary sinus structures, for example, the middle cardiac vein should be considered as potential accessory pathways.

Absent right superior vena cava and persistent left superior vena cava: An incidental finding

A patient with Marfan syndrome undergoing Bentall operation was found to have an absent right superior vena cava and persistent left superior vena cava. The dilation of coronary sinus raised the suspicion of persistent left superior vena cava. The diagnosis was confirmed by agitated saline contrast echocardiography and computed tomography of the chest.

Management of anomalous origin of right coronary artery from left coronary sinus

Aberrant origin of coronary artery is a rare congenital anomaly associated with increased risk of myocardial ischemia and sudden death, with the highest risk lesions being those arising from the opposite sinus of Valsalva. We report a case with an aberrant right coronary artery arising superior to the left coronary cusp, with a slit-like ostium, having an inter-arterial and intramural course through the aortic root, that underwent repositioning of the right coronary artery. We believe such cases warrant surgical correction and reimplantation is a safe, effective and reproducible technique.

Persistent left superior vena cava draining into the unroofed coronary sinus in a patient with tetralogy of Fallot and coronary sinus orifice atresia

INTRODUCTION

In this study, we present a case of directing persistent left superior vena cava drainage into the unroofed coronary sinus to the right atrium in a patient with tetralogy of Fallot and coronary sinus orifice atresia without innominate vein.

CASE REPORT

A 16-month-old boy diagnosed with tetralogy of Fallot was admitted. Following intracardiac repair, the left superior vena cava was divided from the left atrial junction, passed through under the ascending aorta and anastomosed to the right superior vena cava.

CONCLUSION

To our knowledge, this is the first patient reported with persistent left superior vena cava, unroofed coronary sinus, coronary sinus orifice atresia, and tetralogy of Fallot. The extracardiac direct anastomosis technique was used successfully to direct persistent left superior vena cava to the right atrium without any post-procedure complications.

Contrast removal from coronary sinus for prevention of contrast-induced nephropathy: a review

The occurrence of contrast-induced-nephropathy (CIN) is related to the amount of contrast administration. Any removal of contrast from systemic circulation before reaching the kidneys might be beneficial using a device that removes contrast from a coronary sinus (CS). This manuscript aims to review the available literature regarding contrast removal from CS during coronary angiography or intervention for the prevention of CIN.

Coronary flow reserve evaluated by phase-contrast cine cardiovascular magnetic resonance imaging of coronary sinus: a meta-analysis

BACKGROUND

Phase-contrast cine cardiovascular magnetic resonance (CMR) of the coronary sinus has emerged as a non-invasive method for measuring coronary sinus blood flow and coronary flow reserve (CFR). However, its clinical utility has not yet been established. Here we performed a meta-analysis to clarify the clinical value of CMR-derived CFR in various cardiovascular diseases.

METHODS

An electronic database search was performed of PubMed, Web of Science Core Collection, Cochrane Advanced Search, and EMBASE. We compared the CMR-derived CFR of various cardiovascular diseases (stable coronary artery disease [CAD], hypertrophic cardiomyopathy [HCM], dilated cardiomyopathy [DCM]) and control subjects. We assessed the prognostic value of CMR-derived CFR for predicting major adverse cardiac events (MACE) in patients with stable CAD.

RESULTS

A total of 47 eligible studies were identified. The pooled CFR from our meta-analysis was 3.48 (95% confidence interval [CI], 2.98-3.98) in control subjects, 2.50 (95% CI, 2.38-2.61) in stable CAD, 2.01 (95% CI, 1.70-2.32) in cardiomyopathies (HCM and DCM). The meta-analysis showed that CFR was significantly reduced in stable CAD (mean difference [MD] = -1.48; 95% CI, -1.78 to -1.17; p < 0.001; I2 = 0%; p for heterogeneity = 0.33), HCM (MD = -1.20; 95% CI, -1.63 to -0.77; p < 0.001; I2 = 0%; p for heterogeneity = 0.49), and DCM (MD = -1.53; 95% CI, -1.93 to -1.13; p < 0.001; I2 = 0%; p for heterogeneity = 0.45). CMR-derived CFR was an independent predictor of MACE for patients with stable CAD (hazard ratio = 0.52 per unit increase; 95% CI, 0.37-0.73; p < 0.001; I2 = 84%, p for heterogeneity < 0.001).

CONCLUSIONS

CMR-derived CFR was significantly decreased in cardiovascular diseases, and a decreased CFR was associated with a higher occurrence of MACE in patients with stable CAD. These results suggest that CMR-derived CFR has potential for the pathological evaluation of stable CAD, cardiomyopathy, and risk stratification in CAD.

Pressure-Controlled Intermittent Coronary Sinus Occlusion: A Novel Approach to Improve Microvascular Flow and Reduce Infarct Size in STEMI

Despite successful primary percutaneous coronary intervention (PCI) for treatment of ST-segment elevation myocardial infarction (STEMI), myocardial salvage is frequently suboptimal resulting in large infarctions with increased rates of heart failure and death. Microvascular dysfunction after the procedure is frequently present and contributes directly to poor outcomes in STEMI. Pressure-controlled intermittent Coronary Sinus Occlusion (PiCSO) is a novel technology designed to mitigate microvascular dysfunction in STEMI. Non-randomized studies have suggested that PiCSO use during primary PCI in STEMI is safe, improves microvascular perfusion and reduces infarct size. Randomized trials are ongoing to investigate the safety and effectiveness of PiCSO in high-risk patients with anterior STEMI undergoing primary PCI.

Mal-positioned coronary sinus catheter masquerading as right atrium mass - Thanks to transesophageal echocardiography!

Mid esophageal 4 chamber view showing the mass in RA (red arrow) immediately after insertion of coronary sinus catheter. LA, Left atrium; LV, Left Ventricle; RA, Right atrium; RV, Right ventricle.

Atresia of the Midportion of the Coronary Sinus: A Case Report

A 12-year-old with a history of critical pulmonary stenosis and moderate right ventricular hypoplasia underwent neonatal pulmonary valve dilation, an aortopulmonary shunt, and an infant cavopulmonary anastomosis with aortopulmonary shunt takedown. During a diagnostic cardiac catheterization at 12 years of age, angiography showed interruption in the midportion of the coronary sinus, which required no intervention.

Coronary Sinus Reducer Transfemoral Extraction After Intraprocedural Device Migration to the Pulmonary Artery

Coronary sinus reducer migration during implantation is an unusual complication with no standard bailout strategy and to the best of our knowledge there is no description of migration to the pulmonary artery. A mother-and-child technique during implantation could be the safest way to avoid this complication.

Left Atrial Dissection Secondary to Retrograde Coronary Sinus Cannulation During a Stanford Acute Type-A Aortic Dissection Repair: A Case Report

Left atrial (LA) dissections are rare phenomena, often iatrogenic, caused by blood flow into a false lumen, potentially obstructing the pulmonary veins or flow into the left ventricle. Severity can range from an incidental observation or complete circulatory collapse. While LA dissections are often associated with mitral valve repair, there are 2 reported cases of LA dissections associated with retrograde cardioplegia cannula insertion through the coronary sinus. Here, we present a large LA dissection that was directly visualized and tracked to a coronary sinus injury from the retrograde cardioplegia cannula. The clinical presentation and echocardiography findings informed our subsequent management.

Endoscopic Mitral Valve Repair in a Patient With Persistent Left Superior Vena Cava Draining Into the Coronary Sinus - Cannulation Technique and Surgical Management

Persistence of the left superior vena cava is often an incidental finding during cardiac surgical procedures. In minimally invasive valvular surgery, it may jeopardise venous drainage and myocardial protection. This How-To-Do-It paper describes the cannulation strategy in a case of minimally invasive mitral surgery in a patient with persistence of the left superior vena cava and absence of the anonymous vein detected with preoperative multimodality imaging.

Age-adjusted Reference Values and Z-scores of the Coronary Sinus Diameter among Healthy Children and Adolescents in Southern Iran

BACKGROUND

Coronary sinus dimension is an important factor for diagnosing some types of cyanosis as well as congenital heart diseases and insertion of some devices into the coronary sinus if required. This study was designed to access the diameter and Z-score of the coronary sinus among children under 18 years of age.

METHODS

In this cross-sectional study on 95 individuals, the coronary sinus diameter was measured by transthoracic echocardiography in the four-chamber view at the connection to the right atrium, middle part, and distal end. The linear regression equation was utilized to determine age-adjust reference values, Z-scores, and the relationship between the individuals' coronary sinus diameter age, height, and body surface area. The study was conducted from March to July 2020 in Namazi hospital clinic of Shiraz University of Medical Sciences, Shiraz, Iran.

RESULTS

The mean age of the persons who entered this study was 5.87±4.25 years. The mean coronary sinus diameter was 4.91±1.29 mm at the site of connection to the right atrium, 4.50±1.44 mm at the middle part, and 3.74±1.32 mm at the distal end. Coronary sinus diameter correlates positively with the participants' age, weight, height, and body surface area (P<0.001).

CONCLUSION

Coronary sinus diameter significantly correlates with the age, height, and body surface area of the cases. These features are useful in diagnosing some congenital heart diseases and insertion of suitable devices through it.

Insights Into Coronary Sinus Reducer Non-Responders

Refractory angina affects an increasing proportion of the population with advanced coronary artery disease and microvascular dysfunction. Limited effective pharmacological and interventional therapies exist for this patient cohort. The coronary sinus (CS) reducer, recently recommended in the 2019 guidelines of the European Society of Cardiology for the management of chronic refractory angina, is a balloon-expandable, stainless-steel device designed for implantation in the CS. It acts by increasing CS pressure, thereby redistributing blood to ischemic myocardium, relieving symptoms, and improving quality of life. However, between 15%-30% of patients do not respond to this treatment. Six mechanisms appear to explain this poor response to CS reducer therapy: (1) inappropriate patient selection; (2) cardiac venous system heterogeneity; (3) CS size; (4) incomplete device endothelialization; (5) coronary artery disease phenotype and progression; and (6) limited myocardial ischemia at baseline. We hereby review these mechanisms in detail and highlight key areas that should be addressed in order to try and reduce the burden of non-responders following CS reducer implantation.