Ventricular-dependent Coronary Circulation Research Articles

Discussion to: Revascularization of coronary circulation in pulmonary atresia with intact ventricular septum and right ventricular-dependent coronary circulation

Discussion to: Revascularization of coronary circulation in pulmonary atresia with intact ventricular septum and right ventricular-dependent coronary circulation

Follow the MAPCA: an unusual source of right pulmonary artery flow.

Major aortopulmonary collateral arteries in the setting of pulmonary atresia with intact ventricular septum are very rarely encountered, having been documented in only a handful of case reports. We present the right ventriculogram of a patient found to have this rare combination of findings along with right ventricular-dependent coronary artery circulation and unusual supply of the right pulmonary artery.

The Utility of CT Angiography in Neonates with Pulmonary Atresia with Intact Ventricular Septum and Concern for Right Ventricular Dependent Coronary Circulation: Case Series.

Up to one third of patients with pulmonary atresia with intact ventricular septum (PA-IVS) will have inadequate anterograde coronary blood flow and rely on fistulous connections from the right ventricle (RV) for myocardial perfusion, known as RV-dependent coronary circulation (RVDCC). Historically, identification of the extent of ventriculocoronary connections and coronary stenosis has required invasive imaging with cardiac catheterization and angiography. Cardiac computed tomography (CCT) potentially provides a less invasive imaging option for therapeutic planning in this group of patients. We describe six neonates with PA-IVS who underwent both CCT and cardiac catheterization at our institution prior to any surgical or transcatheter intervention between 2009 and 2019. Imaging was concerning for RVDCC in all six patients. The average tricuspid Z-score was - 4.19 (2.1 to - 5.34). Two patients underwent cardiac transplantation and two patients underwent ductal stenting. The overall mortality rate was 50%. CCT findings closely mirrored the findings of invasive cardiac catheterization and identified important morphological variations. The average radiation exposure (DLP) per CCT was (10.5mGycm, range 6-20). Technological improvements in CCT have enabled adequate visualization of coronary anomalies in children with comparable accuracy to cardiac catheterization, but considerably less radiation exposure. However, diagnosis of RVDCC requires direct right ventricular angiography. Therefore, the potential benefit of obtaining a CCT prior to catheterization for infants with PA-IVS is the ability to risk stratify, assist with procedural planning, and improve family counseling.

Outcome Predictors in Catheter Interventions for Severe Right Ventricular Outflow Tract Obstructions.

Introduction & aim of workTranscatheter treatment for critical pulmonary stenosis and membranous pulmonary atresia has become the gold standard of care in many centers. We aimed at evaluating the predictors of outcome in interventions for treatment of duct-dependent right ventricular outflow tract obstruction with intact interventricular septum.Subjects & methods68 cases with pulmonary atresia with intact interventricular septum (PA/IVS) and 50 cases with critical pulmonary stenosis (CPS), all younger than 3 months of age, were operated during the period of 10 years; excluding patients with tricuspid valve annulus Z-score smaller than −4, evidence of right ventricular-dependent coronary circulation or additional malformations.ResultsAge, weight, body surface area as well as tricuspid & pulmonary valve Z-scores were significantly less in PA/IVS; right ventricular pressure was similar in both groups however procedural success and survival to hospital discharge was higher in the CPS group. Lower age, weight and body surface area were associated with procedural failure. Weight was the only predictor of procedural success; while weight and lower post-procedural right ventricular pressure were independent predictors for survival to hospital discharge. Post-procedural right ventricular pressure and length of stay were less in the CPS group. tricuspid and pulmonary valve annulus Z-scores were the only independent predictors of the post-procedural milrinone duration in PA/IVS.ConclusionWe advocate for the use of larger balloon/pulmonary annulus ratio, to achieve a lower right ventricular pressure not fearing excessive pulmonary regurgitation that might be beneficial for right ventricular growth; and for the combination with ductal stenting in borderline or bipartite right ventricles.

This Looks Exactly Like Something I’ve Never Seen Before … or Does It?

The constellation of semilunar valve atresia, important ipsilateral ventricular hypoplasia, intact ventricular septum, and associated anomalies of the coronary arterial tree is rare but well described. Although it occurs with aortic valve atresia, it is more commonly seen with pulmonary valve atresia and is especially difficult to manage if the coronary arteries are obstructed proximally to such an extent as to cause myocardial ischemia. In such cases, the term right ventricular–dependent coronary circulation (RVDCC) is used.

Palliation Plus Ventricular Assist Device Insertion in 15 Neonates and Infants With Functionally Univentricular Circulation

BackgroundWe report 15 high-risk neonates and infants with functionally univentricular circulation stabilized with initial surgical palliation plus ventricular assist device (VAD) insertion (PALLIATION+VAD) in preparation for transplantation. MethodsFifteen functionally univentricular patients with ductal-dependent systemic circulation (8 hypoplastic left heart syndrome, 1 hypoplastic left heart syndrome-related malformation: 7 neonates, 2 infants) or ductal-dependent pulmonary circulation (6 hypoplastic right heart syndrome: 5 neonates, 1 infant) presented with anatomical and/or physiological features associated with increased risk for conventional univentricular palliation (large coronary sinusoids with ventricular-dependent coronary circulation, severe systemic atrioventricular valvar regurgitation, cardiogenic shock, or restrictive atrial septum). PALLIATION+VAD for patients with ductal-dependent systemic circulation was: VAD insertion plus application of bilateral pulmonary bands, stent placement in the arterial duct, and atrial septectomy, if needed. PALLIATION+VAD for patients with ductal-dependent pulmonary circulation was: VAD insertion plus stent placement in the arterial duct or systemic-to-pulmonary artery shunt with pulmonary arterioplasty, if needed. ResultsAt PALLIATION+VAD, median age was 20 days (range, 4-143 days) and median weight was 3.47 kg (range, 2.43-4.86 kg). Ten patients (67%) survived and 5 patients (33%) died. All ten survivors are at home doing well after successful transplantation. Only 2 of 10 survivors (20%) required intubation >10 days after PALLIATION+VAD. Median length of VAD support for all 15 patients was 138 days (range, 56-226 days). ConclusionsHigh-risk neonates with functionally univentricular hearts who are suboptimal candidates for conventional palliation can be successfully stabilized with pulsatile VAD insertion along with initial palliation while awaiting cardiac transplantation; these patients may be extubated, enterally nourished, and optimized for transplantation while on VAD.

Infants with pulmonary atresia intact ventricular septum who require balloon atrial septostomy have significantly higher 18-month mortality.

Many newborns with pulmonary atresia/intact ventricular septum require intervention to establish pulmonary flow and sufficient cardiac output. The resulting haemodynamic changes are not well characterised and may have unintended consequences. This is a 30-year (1988-2018) retrospective study of patients with pulmonary atresia intact ventricular septum. Eighty-nine patients were included, and median follow-up was 8 years. Fifty-five per cent had coronary sinusoids and 27% had right ventricular-dependent coronary circulation. Most patients were managed with surgical aortopulmonary or modified Blalock-Taussig shunt (73%), and 12 patients underwent balloon atrial septostomy before surgical intervention. The remaining patients (27%) underwent only transcatheter interventions; 7 required an atrial septostomy and 17 required ductal stentings. All-cause mortality was 10%, most deaths (89%) occurred before 18 months of age. Of these early deaths, 87% required a balloon atrial septostomy and 85% had right ventricular-dependent coronary sinusoids. Eighteen-month mortality was significantly higher for patients who required a balloon atrial septostomy compared to those who did not (36% versus 1.4% p < 0.0001). Patients with pulmonary atresia/intact ventricular septum who require balloon atrial septostomy in the newborn period have significantly higher 18-month mortality. Quantifying the mortality difference may help guide prognostication and expectation setting. Infants who had septostomy and a surgical shunt in the newborn period fared better than those who only underwent septostomy (even when accompanied by ductal stenting). For infants with right ventricular-dependent circulation, atrial septostomy should only be performed on an urgent or emergent basis and these patients should be considered for early surgical intervention and neonatal transplant.

Pulmonary Atresia With Intact Ventricular Septum With Borderline Tricuspid Valve: How Small Is Too Small.

PA/IVS is a rare, heterogenous congenital heart defect anatomically defined by complete obstruction to the right ventricular outflow tract with varying degrees of hypoplasia of the right ventricle and tricuspid valve. This lesion can have associated coronary artery anomalies and, in some cases, right ventricular-dependent coronary circulation. Due to the wide spectrum of presenting anatomic and clinical features, the treatment options are often dictated by the degree of development of the tricuspid valve and right ventricle. The purpose of this review is to discuss the spectrum of pulmonary atresia with intact ventricular septum morphologies and to evaluate the surgical decision-making process and approaches to surgical repair with respect to the impact of hypoplastic right-sided cardiac features.

Transthoracic Echocardiographic Assessment of Coronary Flow in the Diagnosis of Right Ventricular-Dependent Coronary Circulation in Pulmonary Atresia with Intact Ventricular Septum

Right ventricular-dependent coronary circulation (RVDCC) is associated with pulmonary atresia with intact ventricular septum and is defined by two or more epicardial coronary arteries with atresia or severe stenosis resulting in the dependency of coronary supply by retrograde flow. The hypothesis of this study is that coronary Doppler flow patterns on echocardiography can be used to distinguish patients with RVDCC. Between 2007 and 2016, we reviewed 16 patients with pulmonary atresia or critical pulmonary stenosis. Patients were divided into two groups, those with RVDCC (determined by angiography or pathology evaluation) and those without. Echocardiographic evaluation of the coronary arteries included 2-dimensional measurements and pulse wave Doppler flow pattern in 3 epicardial coronary arteries. Velocity-time integral (VTI) and maximal velocity (Vmax) were measured and compared between the two groups. Three coronary flow patterns were demonstrated: (1) all antegrade flow, (2) antegrade to retrograde VTI flow ratio > 1, and (3) antegrade to retrograde VTI flow ratio ≤ 1. Of the 7 patients with RVDCC, 6 (86%) had evidence of flow pattern 3 in ≥ 2 of the 3 coronary arteries in contrast to 0 (0%) of the non-RVDCC patients (p = 0.001). Higher retrograde Vmax was associated with RVDCC (p < 0.001) and coronary artery dilatation with Z-score ≥ + 3 was also associated with RVDCC (p = 0.02). Echocardiographic evaluation of the coronaries can be useful in identifying RVDCC. More retrograde flow in at least two coronary arteries is strongly suggestive of RVDCC. Dilatation of the coronary arteries is also supportive evidence.

Transcatheter pulmonary valve perforation using chronic total occlusion wire in pulmonary atresia with intact ventricular septum

Background:Perforation of pulmonary valve using radiofrequency ablation in pulmonary atresia with intact ventricular septum (PA IVS) is a treatment of choice. However, significant cost of the equipment limits its utility, especially in the developing economies.Objective:To assess the feasibility, safety, and efficacy of perforation of pulmonary valve using chronic total occlusion (CTO) wires in patients with PA IVS as an alternative to radiofrequency ablation.Methods:This is a single-center, nonrandomized, retrospective study conducted during June 2008 to September 2015. Twenty-four patients with PA IVS were selected for the procedure during the study period. The median age and weight of the study population were 8. days and 2.65 kg, respectively. Four patients were excluded after right ventricular angiogram as they showed right ventricular-dependent coronary circulation. The pulmonary valve perforation was attempted using various types of CTO wires based on the tip load with variable penetrating characteristics.Results:The procedure was successful in 16 of twenty patients using CTO wires: Shinobi in nine, Miracle in four, CROSS-IT in two, and Conquest Pro in one. Two patients had perforation of right ventricular outflow tract (RVOT). Pericardiocentesis was required in one patient to relieve cardiac tamponade. Later, the same patient underwent successful hybrid pulmonary valvotomy. The other patient underwent ductus arteriosus (DA) stenting. Balloon atrial septostomy was needed in three cases with systemic venous congestion. Desaturation was persistent in five cases necessitating DA or RVOT stenting to augment pulmonary blood flow. There were two early and two late deaths. The mean follow-up was 22.66 ± 16 months. Three patients underwent one and half ventricle repair and one Blalock–Taussig shunt during follow-up.Conclusion:Perforation of the pulmonary valve can be done successfully using CTO wires in selected cases of pulmonary atresia with intact ventricular septum.

Pulmonary atresia with intact ventricular septum and right ventricular dependent coronary circulation through the “vessels of Wearn”

We present an autopsy case of a male baby born at 35 weeks of gestation with pulmonary atresia with intact ventricular septum (PAIVS), who had coronary blood flow that was dependent on outflow from the right ventricle through the vessels described by Wearn. At 7 weeks of age, he underwent single ventricle palliation consisting of ligation of a patent ductus arteriosus and placement of a modified Blalock-Taussig shunt. The patient experienced a perioperative myocardial infarction, requiring extracorporeal membrane oxygenation. Progressive hemodynamic decline resulted in death 8 days after surgery. Autopsy revealed acute and remote infarctions in both ventricles and fibromuscular dysplasia of the subepicardial and intramural coronary arteries. In 1926, Grant first reported the association between PAIVS and secondary dysplasia of the heart vasculature and hypothesized that the high pressure resulted in dilation of the myocardial sinusoids. Confusion secondary to the unmeritorious dismissal of the myocardial sinusoids has obscured the pathogenesis of PAIVS and led to several publications suggesting second heart field abnormalities as a disease model for PAIVS. We discuss the pathogenesis of PAIVS, the ventriculocoronary arterial connections and the sinusoidal relationship to the vessels described by Wearn, and we attempt to correct the solecism plaguing the nomenclature of myocardial vasculature.

When coronary arteries need systolic pressure: surgical considerations

Patients with pulmonary atresia and intact ventricular septum (PA-IVS) may have coronary sinusoids connected to a hypertensive right ventricle. Coronary perfusion may then completely depend on the right ventricular systolic pressure wave; decompression of the right ventricle can be deleterious in these patients. This study was set to investigate the treatment strategies and outcomes of patients with coronary sinusoids. National multicentre retrospective analysis over 15 years (1985-2010) in a population of ~10.2 million people. All patients with PA-IVS and coronary sinusoids were identified from local databases. All angiograms, echocardiograms, surgical reports and outcome data were reviewed. Thirty patients were identified. Right ventricular-dependent coronary circulation was present in nine patients (30%). A systemic-to-pulmonary artery shunt was created in 23 patients (77%) at a median age of 13.0 days (range: 1-479). A bidirectional Glenn was performed in 20 children at a median age of 7.8 months (range: 2.1-112.9) and 11 children proceeded to a Fontan repair at a median age of 3.6 years (range: 2.1-19.6). Pulmonary valve perforation and angioplasty were performed in six children and in three a simultaneous decompression procedure was also done. Ten patients died (33%). Four died at the time of systemic-to-pulmonary artery shunt and three during the bidirectional Glenn shunt. In all these patients myocardial ischaemia was reported. Mortality in PA-IVS with sinusoids is high. Right ventricular coronary dependence may lead to early death if the right ventricular systolic pressure wave is interrupted. Adequate understanding of the underlying pathology and pathophysiology is essential before attempting any procedure in this subgroup of children.

Acquired ventricular septal aneurysm in a patient with pulmonary atresia with intact ventricular septum

Myocardial ischaemia and infarction in pulmonary atresia and intact ventricular septum with right ventricular-dependent coronary circulation is a well-established complication. We report an interesting case of an acquired aneurysm in the ventricular septum in a patient who underwent staged palliation.

Hybrid Therapy for Pulmonary Atresia With Intact Ventricular Septum

In patients with pulmonary atresia with intact ventricular septum without right ventricular-dependent coronary circulation, catheter techniques, including the use of a stiff wire, lasers, and radiofrequency, have been most widely used for initial therapy; however, percutaneous perforation and balloon valvuloplasty have been associated with higher rates of procedural failure and serious complications. We report our experience with a hybrid approach involving the combination of surgery and interventional catheterization techniques for right ventricular decompression. Between March 2005 and April 2010, we performed a hybrid procedure in 30 newborns and infants (age, 1 day to 2 years; median age, 3 months) with favorable anatomy. The heart was exposed by performing midline sternotomy. A purse-string suture was placed in the right ventricular outflow tract 2 cm away from the pulmonary trunk. Then, a 16-gauge intravenous catheter was placed periventricular with the guidance of echocardiography to perforate the atretic pulmonary ventricle. Subsequently, a guide wire was inserted into the sheath and used to guide a balloon across the pulmonary ventricle. Sequential dilations were performed under the guidance of epicardial echocardiography until full opening of the pulmonary ventricle was obtained. In newborns, ductal ligation was performed, followed by modified Blalock-Taussig (mBT) shunt placement. Patients aged greater than 1 month were treated mostly with ductal ligation, and an mBT shunt was inserted if severe systemic oxygen desaturation occurred after ductal ligation; bidirectional Glenn shunt placement was performed if a patient showed severe hypoplasia. The hybrid procedure was successfully performed in all patients. Patent ductus arteriosus ligation was simultaneously performed in 27 cases. Six newborns were treated with mBT shunt placement after pulmonary valvuloplasty and patent ductus arteriosus ligation, and 2 patients aged greater than 1 month were treated with mBT shunt placement alone. Another 2 patients were selected for univentricular palliation with bidirectional Glenn procedure because of a diminutive monopartite right ventricle. No pericardial effusion or cardiac tamponade was observed. One patient in whom ductal ligation could not be performed was treated with mBT shunt placement because of hypoxemia 3 days after the hybrid procedure; the other patients were discharged without any further surgical intervention. During the follow-up period of 1.5 months to 5 years, 5 patients died; 25 (83.3%) survived and all were in New York Heart Association functional class 1. Saturation of peripheral oxygen in the survivors increased from 73.1±8.5% to 94±3.5% (p<001). Two-ventricle circulation was achieved in 24 patients, whereas 1 patient had a single-ventricle pathway. In conclusion, periventricular balloon pulmonary valvuloplasty using a hybrid approach was safe and feasible for patients with pulmonary atresia with intact ventricular septum.

Invited Commentary

Invited Commentary

Paroxysmal complete atrioventricular block in a patient with pulmonary atresia and intact ventricular septum

Sudden death in pulmonary atresia and intact ventricular septum with right ventricular dependent coronary circulation is a well-established complication, and is thought to be caused by myocardial ischaemia. We report a case of paroxysmal complete atrioventricular block that raises the possibility of an additional mechanism of sudden death.

Midterm Results for Collaborative Treatment of Pulmonary Atresia With Intact Ventricular Septum

We report a single-institution experience using a collaborative surgical and catheter-based approach to the initial treatment of pulmonary atresia with intact ventricular septum. A retrospective review was conducted of all neonates admitted with pulmonary atresia with intact ventricular septum from 1996 to March 2007. We identified 24 patients with a mean age at first intervention of 4.5 days with mean follow-up of 6.05 years (range, 1.9 to 12.7 years). Initial palliation was determined by right ventricular size, morphology, and presence or absence of right ventricular-dependent coronary circulation. Initial catheter-based pulmonary valve perforation and valvuloplasty was performed in 41.7% (10 of 24 patients; group A), and 58.3% (14 of 24 patients) had an initial systemic-to-pulmonary artery shunt (group B). Tricuspid valve size was significantly smaller in group B (median z-score, -0.52 group A versus -2.40 group B; p < 0.001). Placement of a shunt after valvuloplasty in group A was required in 70.0% (7 of 10 patients). There was no mortality in group A, and 70.0% (7 of 10 patients) are in a two-ventricle pathway and 30.0% (3 of 10 patients) are in a 1.5-ventricle pathway. Group B had mortality of 14.3% (2 of 14 patients), both within 5 days of surgery. All group B patients remain in a single-ventricle pathway. Overall survival is 91.7% (22 of 24 patients). An individualized approach to this complex lesion has good results. If the right ventricle can be safely decompressed and appears usable, the need for a shunt after valvuloplasty does not preclude two-ventricle (or 1.5-ventricle) repair. Anatomy mandating a shunt as initial palliation has substantial early mortality.

Persistent Thebesian Sinusoids Presenting as Ischemic Heart Disease

A 54-year-old man with no significant past medical history or modifiable cardiovascular risk factors was admitted with chest pains and palpitations. ECG revealed atrial fibrillation with fast ventricular response that reverted to sinus rhythm after intravenous administration of digoxin. His 12-hour troponin I level was marginally elevated (0.07 ng/mL; normal range <0.06 ng/mL). Subsequent serial 12-lead ECGs (Figure 1) demonstrated widespread dynamic ST-segment and T wave changes. The patient was treated for an acute coronary syndrome and became pain free on intravenous administration of glyceryl trinitrate and glycoprotein IIB/IIIA antagonist. Coronary angiography demonstrated pristine epicardial coronaries but a bizarre appearance of capillary blush draining into the left venticular cavity, during both left main stem and right coronary artery injection (Figure 2A and 2B and Movie I and II). In absence of any myocardial tumor, ventricular hypertrophy, or …

The prevalence of coronary arterial abnormalities in pulmonary atresia with intact ventricular septum and their influence on surgical results

The relatively high mortality in patients with pulmonary atresia and intact ventricular septum may be related to the presence of significant coronary arterial anomalies. This retrospective review of cineangiocardiograms was undertaken to further elucidate the types and variety of such coronary arterial abnormalities, and to assess their effect on postoperative survival. Details regarding coronary arterial anatomy and abnormalities were assessed in 116 patients. We noted the site and severity of lesions, and the presence of fistulous communications from the right ventricle to the coronary arteries, assessing the proportion of left ventricular myocardium affected by coronary arterial interruptions or significant stenoses, in other words, the amount dependent on coronary circulation from the right ventricle. We also measured diameters of the tricuspid and mitral valves. Fistulas were found in 87 patients (75%), interruptions of major coronary arteries in 40 patients (34%), lack of connections between the coronary arteries and the aorta in 18 patients (16%), and single origin of a coronary artery, with the right coronary artery arising from the left, in 6 patients (5%). We found increased mortality in 47 patients (40%) who had a right ventricular-dependent coronary arterial circulation. The presence of fistulas in itself was not associated with higher mortality, but the presence of coronary arterial interruptions (p = 0.05), and a higher myocardial score (p = 0.0009), were. We encountered a higher prevalence of both coronary arterial abnormalities and right ventricular-dependent circulation than previously reported. Awareness of the severity of the coronary arterial abnormalities should assist in planning treatment.

Fetal Tricuspid Valve Size and Growth as Predictors of Outcome in Pulmonary Atresia With Intact Ventricular Septum

Pulmonary atresia with intact ventricular septum is a complex congenital cardiovascular anomaly that frequently requires single ventricle palliation. Fetal diagnosis of pulmonary atresia with intact ventricular septum is common, but the natural history of pulmonary atresia with intact ventricular septum diagnosed in midgestation, predictors of neonatal anatomy, and predictors of biventricular repair have not been determined. The objective of this study was to determine whether the size and rate of growth of the fetal tricuspid valve predict neonatal anatomy and biventricular repair. Twenty-three fetuses diagnosed with pulmonary atresia with intact ventricular septum between 1990 and 2004 were studied. Of 13 fetuses with a midgestation fetal tricuspid valve z score < or = -3, 1 achieved biventricular repair, compared with 5 of 5 with a tricuspid valve z score > -3. Of 13 fetuses with a midgestation fetal tricuspid valve z score < or = -3, 8 were diagnosed postnatally with a right ventricular dependent coronary circulation, compared with none with a tricuspid valve z score > -3. Midgestation and late gestation fetal tricuspid valve z scores correlated with neonatal tricuspid valve z score. The average rate of tricuspid valve growth between mid- and late fetal echocardiograms was significantly lower in patients who did not achieve biventricular repair than in those who did (0.012 +/- 0.008 cm per week vs 0.028 +/- 0.014 cm per week). Fetal tricuspid valve z score and rate of growth predict postnatal outcome in pulmonary atresia with intact ventricular septum. These findings may have important implications for prenatal counseling and selection of patients for fetal pulmonary valve dilation.