Successful coil embolization of a large right coronary artery-coronary sinus fistula causing a significant left-to-right shunt: a case report.

BACKGROUND: This case reviews a challenging but successful transcatheter coil embolization of a large congenital coronary artery fistula (CAF) causing a significant left-to-right shunt. CASE SUMMARY: A 51-year-old female with no significant prior history presented with symptoms of dyspnoea and chest discomfort. Extensive evaluation revealed a large CAF between a tortuous right coronary artery (RCA) and the coronary sinus (CS) composed of three aneurysmal pseudochambers. Closure of the RCA-CS fistula was attempted through coil deployment into the fistula neck. However, due to the brisk flow through the fistula, both coils embolized into the fistula sac. An alternative location was subsequently identified on three-dimensional rendering of a computed tomography angiography scan, which revealed a sharp bend in the RCA prior to the fistula neck and distal to the posterior descending artery (PDA) takeoff. Repeat attempt at embolization was accomplished using a telescoping system to reach and occlude the targeted bend. The coil mass remained stable and angiography demonstrated reduced flow through the fistula and preserved patency of the PDA. The decreased residual flow through the fistula secondary to the initial embolization attempt likely aided the successful deployment of coils in the second and final attempt. At 1 year, the patient was doing well with resolution of her symptoms and no clinical symptoms of coronary ischaemia. DISCUSSION: We suggest that an initial unsuccessful attempt at transcatheter embolization of a CAF should not preclude subsequent attempts for closure when there exists an appropriate indication.

PET/CT Myocardial Perfusion Imaging Acquisition and Processing: Ten Tips and Tricks to Help You Succeed.

PURPOSE OF REVIEW: Positron emission tomography (PET) is a leading non-invasive modality for the diagnosis of coronary artery disease due to its diagnostic accuracy and high image quality. With the latest advances in PET systems, clinicians are able to assess for myocardial ischemia and myocardial blood flow while exposing patients to extremely low radiation doses. This review will focus on the basics of acquisition and processing of hybrid PET/CT systems from appropriate patient selection to common artifacts and pitfalls. RECENT FINDINGS: The continued development of hybrid PET/CT technology is producing scanners with exquisite sensitivity capable of generating high-quality images while exposing patients to low radiation doses. List mode acquisition is an essential component in all modern PET/CT scanners allowing simultaneous dynamic and ECG-gated imaging without lengthening scan duration. Various PET radiotracers are currently being developed but rubidium-82 and 13N-ammonia remain the most commonly used perfusion radiotracers. The development of mini 13N-ammonia cyclotrons is a promising tool that should increase access to this radiotracer. Misregistration, attenuation from extra-cardiac activity, and patient motion are the most common causes of artifacts during perfusion imaging. Techniques to automatically realign images and correct respiratory or patient motion artifacts continue to evolve. Despite the continuous evolution of PET imaging techniques, basic knowledge of scan parameters, acquisition techniques, and post processing tools remains essential to ensure high-quality images are produced and artifacts are recognized and corrected. Future research should focus on optimizing scanners to allow for shorter scan protocols and lower radiation exposure as well as continue developing techniques to minimize and correct for motion and misregistration artifacts.

Transitioning From Room to Zoom: The 2020 Cardiovascular Fellows' Boot Camp in the COVID-19 Era.

For 10 years, the annual Houston Methodist Cardiovascular Fellows' Boot Camp hosted hundreds of cardiovascular trainees in Houston for a concise yet comprehensive 3-day training program for new fellows. The cornerstone of the program was the hands-on Skills Academy, which included a variety of timed learning stations that taught surgical techniques, dissection skills, and suturing techniques as well as echocardiography and cardiac catheterization using simulators. This was followed by 2 days of didactics covering essential topics in each specialty. However, that model was upended in 2020 by the COVID-19 pandemic. The pandemic forced the digitization of medical education and posed significant challenges as we transitioned Boot Camp to a virtual format. In this editorial, we review our experience designing and implementing a virtual cardiology track of the Houston Methodist Cardiovascular Fellows' Boot Camp and highlight challenges and proposed solutions in the era of virtual education.

Cardiovascular Implications of COVID-19 Infections.

Since early 2020, the world has been facing a pandemic caused by the novel coronavirus SARS-CoV-2. Although this positive single-stranded RNA virus primarily causes pulmonary infection and failure, it has been associated with multiple cardiovascular diseases including troponin elevation, myocarditis, and cardiac arrhythmias. Cardiac patients are susceptible to developing more severe infection from SARS-COV-2, making management complicated. In this review we discuss the cardiac manifestations of COVID-19 infections as well as considerations for the management of primary cardiac pathologies during this pandemic.

Building an Adult Congenital Heart Program: Critical Components and Important Allies.

PURPOSE OF THE REVIEW: The purpose of this review is to illustrate specific challenges and opportunities in the building of an adult congenital heart disease (ACHD) program and to highlight critical components and important allies. RECENT FINDINGS: With more than 1.4 million adults with congenital heart disease in the USA alone, access to specialized, compassionate, high-quality comprehensive care requires a shift toward more aggressive expansion of ACHD care, especially in the context of sparse ACHD provider representation in the vast majority of adult medical centers. The effective build of an ACHD program requires measured escalation in management of ACHD complexity matched with cultivation of key resources and clinical services ranging from congenital cardiac surgery and interventional cardiology to acquired heart disease as well as partnerships with non-cardiac specialists. By reframing ACHD care as a shared goal between patients, providers, hospitals, pharmaceutical and device industry, and payers, a potent business model can be built around the developing ACHD program to facilitate acquisition of these key resources.

Transcatheter closure of a sinus venosus atrial septal defect using 3D printing and image fusion guidance.

A 63-year-old man with cirrhosis, hepatocellular carcinoma, and coagulopathy was diagnosed with a sinus venosus atrial septal defect (ASD) and partial anomalous pulmonary venous return (PAPVR) of the right upper pulmonary vein (RUPV). Transcatheter repair by positioning a stent graft in the superior vena cava was planned. Based on three-dimensional (3D) reconstruction of gated cardiac CTA, a 28 mm × 7 cm Endurant II® aortic extension stent graft (Medtronic, MN) was chosen. A 3D model printed from the CTA was used to simulate device deployment, demonstrating successful exclusion of the sinus venosus ASD with return of the RUPV to the left atrium (LA). Post simulation, the 3D model was used for informed consent. The patient was then taken to the hybrid operating room. On-table cone beam CT was performed and registered with the CTA images. This enabled overlay of 3D regions of interest to live 2D fluoroscopy. The stent graft was then deployed using 3D regions of interest for guidance. Hemodynamics and angiography demonstrated successful exclusion of the sinus venosus ASD and unobstructed return of RUPV to the LA. This is the first report of comprehensive use of contemporary imaging for planning, simulation, patient consent, and procedural guidance for patient-centered complex structural intervention in repair of sinus venosus ASD with PAPVR. We propose this as a process model for continued innovation in structural interventions.

Adult congenital heart disease: magnitude of the problem.

PURPOSE OF REVIEW: To define the magnitude of problems faced by patients with adult congenital heart disease (ACHD) and to identify unmet needs for this population. RECENT FINDINGS: The ACHD population is estimated to include more than 1 million people in the United States and continues to grow at a steady rate. Owing to the decline in early mortality in this group, modern medicine is now faced by the long-term complications associated with congenital heart disease such as chronic heart failure, increased endocarditis risk, elevated burden of arrhythmias, pulmonary hypertension, valvular dysfunction, and pregnancy. SUMMARY: Increasing access to ACHD care, evolution of imaging techniques and transcatheter technology and continued efforts at quality improvement will be key to successfully facing the challenges that are a product of the astounding success of pediatric cardiac surgery.

Imaging adult patients with coarctation of the aorta.

PURPOSE OF REVIEW: To provide an overview of current recommendations and techniques used to image coarctations of the aorta. RECENT FINDINGS: Imaging of coarctation of the aorta in adults is moving away from conventional techniques such as echocardiography and invasive angiography. Echocardiography may assist in making the diagnosis but is limited in its ability to quantify the severity of coarctations. Current guidelines recommend that every patient with a coarctation must undergo a computed tomography (CT) or MRI scan for accurate delineation of morphology. MRIs provide important hemodynamic data and this is rapidly evolving to include techniques such as 4D flow cardiac MRI which can provide time-resolved data; research on using MRIs in the interventional suite is underway. CT is important for surveillance and provides detailed information about repair-site anatomy. Additionally, the use of CT-based technology to guide transcatheter interventions may improve the safety and efficiency of angioplasty and stent deployment. SUMMARY: Although echocardiography is an important first line means to establish the diagnosis of aortic coarctations, CT and MRI-based techniques enable the provision of patient-specific management options, can guide transcatheter interventions and detect long-term post-intervention complications.

Rapid Left Ventricular Recovery After Correction of a Secundum Atrial Septal Defect: Understanding the Hemodynamics.

Closure of an atrial septal defect (ASD) may lead to a change in the function of both ventricles. Although right ventricular function typically improves, the left ventricle (LV) may behave in different ways. This has been a matter of much debate, with some authors reporting a decline in LV function after ASD closure and others reporting delayed improvement or no identifiable change. We report the case of a 41-year-old female with a large left-to-right ASD shunt (Qp:Qs 2.3:1 and shunt volume 3.6 L/min) who presented with biventricular systolic dysfunction that improved within 24 hours of ASD closure. We also attempt to explain the underlying hemodynamics responsible for LV failure and recovery in this patient.

Neonatal diabetes mellitus due to a novel ABCC8 gene mutation mimicking an organic acidemia.

Neonatal diabetes mellitus and organic acidemias, may present with similar features like hyperglycemia, ketoacidosis and failure to thrive. A four-mo-old girl presented with diabetic ketoacidosis following a febrile respiratory illness during which high anion gap metabolic acidosis and hyperglycemia were detected. She also had hyperammonemia, which led to diagnostic uncertainty. Euglycemia was achieved with insulin injections. Genotyping revealed a homozygous novel mutation of the ABCC8 gene coding for the SUR1 subunit of the pancreatic beta cell potassium channel. Subsequently, the child was successfully transitioned to oral glibenclamide therapy. Developmental delay was noted on follow-up which raised the possibility of intermediate DEND syndrome. A possible cause for hyperammonemia in neonatal diabetes mellitus has been postulated in the discussion.

Association of CYP2C9 polymorphisms with phenytoin toxicity in Indian patients.

BACKGROUND: Genetic polymorphisms of CYP2C9 can lead to wide inter-individual variations in drug metabolism. Decreased metabolism leads to higher plasma levels, causing adverse drug reactions (ADRs). Polymorphic alleles CYP2C9 FNx01 2 and CYP2C9 FNx01 3 occur in the Indian population and this may serve as the basis for using genotyping as a tool to predict phenytoin toxicity. AIMS: To evaluate the association between the presence of polymorphic alleles CYP2C9 FNx01 2 and FNx013 and phenytoin toxicity in Indian patients with epilepsy. SETTINGS AND DESIGN: A case-control study with cases defined as those who had plasma phenytoin concentrations above 20 µg/ml. MATERIALS AND METHODS: The study population included 259 patients with epilepsy on phenytoin. Phenotyping was done using High Performance Liquid Chromatography. Those with plasma phenytoin levels above 20 µg/ml were taken as cases and the rest as controls. Genotyping was done by Polymerase Chain Reaction - Restriction Fragment Length Polymorphism. STATISTICS: Numerical data between groups was compared using unpaired-'t' test. Between-group comparison of categorical data was done using Chi square for trend with crude odds ratio (OR). Adjusted OR was calculated using binary logistic regression. RESULTS: There were 40 cases and 219 controls. Mean phenytoin dosage between groups was not statistically significant. Of the 40 cases, 25 (62.5%) cases had wild alleles versus 178 (81.3%) controls. We found a significant association between polymorphic alleles CYP2C9 FNx01 2 and FNx013 and toxic phenytoin levels. After adjusting for age, sex and dose, a significant association between polymorphic alleles and phenytoin toxicity was still found. CONCLUSIONS: This study shows significant association between polymorphic alleles and phenytoin toxicity in this study population. However, until technology for genotyping becomes cost-effective, we would recommend Therapeutic Drug Monitoring to guide dosing.