Progenitor Cell Function and Cardiovascular Remodelling Induced by SGLT2 Inhibitors.

Sodium-glucose cotransporters 2 (SGLT2) are high-capacity, low-affinity transporters, expressed mainly in the early portion of the proximal renal tube, mediating up to 90% of renal glucose uptake, while SGLT1 receptors are found mainly in the small intestine, facilitating glucose absorption. SGLT2 inhibitors (SGLT2i) originally emerged as agents for the treatment of type 2 diabetes mellitus; however, they soon demonstrated remarkable cardio- and renoprotective actions that led to their licensed use for the treatment of heart failure and chronic kidney disease, regardless of the diabetic status. Cardiovascular remodelling represents an umbrella term that encompasses changes that occur in the cardiovascular system, from the molecular and cellular level, to tissue and organs after local injury, chronic stress, or pressure. SGLT modulation has been shown to positively affect many of these molecular and cellular changes observed during pathological remodelling. Among the different pathophysiological mechanisms that contribute to adverse remodelling, various stem and progenitor cells have been shown to be involved, through alterations in their number or function. Recent studies have examined the effects of SGLT2i on stem and progenitor cell populations and more specifically on endothelial progenitor cells (EPCs). Although some found no significant effect, others showed that SGLT2i can modulate the morphology and function of EPCs. These preliminary observations of the effect of SGLT2i on EPCs may be responsible for some of the beneficial effects of gliflozins on pathological remodelling and, by extension, on cardiovascular disease. The purpose of this narrative review is to critically discuss recent evidence on the cardioprotective effects of SGLT2is, in the context of cardiac remodelling.

Current knowledge and contemporary management of non-A non-B aortic dissections.

Non-A non-B aortic dissection (AAD) is an infrequently documented condition, comprising of only a small proportion of all AADs. The unique anatomy of the aortic arch and the failure of the existing classifications to adequately define individuals with non-A non-B AAD, have led to an ongoing controversy around the topic. It seems that the clinical progression of acute non-A non-B AAD diverges from the typical type A and B dissections, frequently leading to serious complications and thus mandating early intervention. Currently, the available treatment methods in the surgical armamentarium are conventional open, endovascular techniques and combined hybrid methods. The optimum approach is tailored in every individual case and may be determined by the dissection's location, extent, the aortic diameter, the associated complications and the patient's status. The management of non-A non-B dissections still remains challenging and a unanimous consensus defining the gold standard treatment has yet to be reached. In an attempt to provide further insight into this perplexing entity, we performed a minireview of the literature, aiming to elucidate the epidemiology, clinical course and the optimal treatment modality.

Mitral Annular Disjunction: Pathophysiology, Pro-Arrhythmic Profile and Repair Pearls.

Mitral annular disjunction (MAD) is a structural abnormality defined by a distinct separation of the mitral valve annulus-left atrial wall continuum and the basal aspect of the posterolateral left ventricle. This anomaly is often observed in patients with myxomatous mitral valve prolapse. Importantly, MAD has been strongly associated with serious ventricular arrhythmias and predisposes to sudden cardiac death. Therefore, we have to emphasize the need to diagnose this morphologic and functional abnormality in routine practice in order to facilitate optimal mitral valve repair and minimize patient risks. Nevertheless, clinical knowledge regarding MAD still remains limited. In the present review, we aim to shed light on several aspects of MAD, including distinct anatomical and pathophysiological characteristics, imaging modalities, association with ventricular arrhythmias, and current methods of treatment.

An alternative approach for complicated prosthetic aortic valve endocarditis.

BACKGROUND: Surgical treatment of prosthetic valve endocarditis (PVE) with destruction of the aortic root and aortomitral continuity is demanding even in experienced hands. CASE PRESENTATION: Herein, we describe a case of a 71-year-old female patient who presented with PVE that was further complicated by a fistulous abscess cavity. The patient underwent removal of the dehisced prosthetic valve, radical annular debridement, reconstruction of the aortomitral curtain with a pericardial patch as a patch exclusion technique and implantation of a sutureless valve. CONCLUSION: Patch exclusion technique, followed by sutureless valve implantation, might represent a feasible and safe alternative for the surgical treatment of complicated PVE.

Surgical repair of anomalous aortic origin of coronary artery in adults.

Anomalous aortic origin of a coronary artery is a congenital abnormality of the origin or course of a coronary artery that arises from the aorta. The surgical treatment of this anomaly is highly variable and controversial and is achieved by implementing elaborate techniques of anatomic repair or by simple coronary artery bypass grafting. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Two independent reviewers determined whether studies met the inclusion criteria. Eligible papers were published in English, clinical studies describing surgical repair of anomalous aortic origin of a coronary artery including coronary artery bypass in adults, and enrolled >5 patients. In the absence of multicentre trials, 7 single-center retrospective series were included, which demonstrated comparable short- and midterm outcomes of anatomic repair and coronary artery bypass in adults with anomalous aortic origin of a coronary artery. Coronary unroofing was the preferred technique when the anomalous artery has an intramural component, but there is a risk of aortic insufficiency. Anatomic repair is technically demanding and should be carried out in experienced centers. Coronary artery bypass with internal thoracic artery or vein grafts is technically straightforward with low operative risk and comparable midterm outcomes, however, long-term outcomes are unknown. Coronary artery bypass grafting is the technique of choice for older patients, in those with concomitant coronary artery disease, as a bailout procedure for failed anatomic repair, or in centers without experience in anatomic repair for anomalous aortic origin of a coronary artery.

Cardio-Protective Effects of Sodium-Glucose Co-Transporter 2 Inhibitors: Focus on Heart Failure.

BACKGROUND: Type 2 diabetes mellitus (DM) is associated with a considerable risk of cardiovascular and renal diseases, including heart failure. Sodium-glucose co-transporter 2 (SGLT2) inhibitors have demonstrated unprecedented cardiorenal protective effects in large-scale clinical trials of patients with or without diabetes and either established cardiovascular disease (CV) or multiple CV risk factors. OBJECTIVE: Herein we aim to focus on the role of SGLT2 inhibitors regarding the improvement in heart failure outcomes and the proposed mechanisms of action by which these drugs confer their beneficial effect. METHODS: PubMed, Embase, and Google Scholar databases were searched to identify eligible articles that are comprehensively summarized and discussed in this study. RESULTS: The most commonly discussed mechanisms of action are diuresis and natriuresis, reduction in preload, afterload, and ventricular mass, as well as stimulation of erythropoietin production and improved myocardial energetics. SGLT2 inhibitors improve outcomes in patients with established heart failure (HF) and reduce the risk of death and HF admissions in patients with established chronic HF with reduced ejection fraction (HFrEF), either with or without diabetes. CONCLUSION: Potential key mechanisms that may explain the notable cardioprotective benefits of SGLT2 inhibitors have been outlined. These agents have recently received class Ia recommendation in specific groups of people with DM to lower the risk of hospitalization for HF and risk of death, while these benefits may also extend to people without diabetes. It remains to be seen whether they will also emerge as treatment approaches in the acute phase of CV episodes.

Rapid right ventricular pacing for balloon valvuloplasty in congenital aortic stenosis: A systematic review.

BACKGROUND: Balloon aortic valvuloplasty (BAV) is a well-established treatment modality for congenital aortic valve stenosis. AIM: To evaluate the role of rapid right ventricular pacing (RRVP) in balloon stabilization during BAV on aortic regurgitation (AR) in pediatric patients. METHODS: A systematic review of the MEDLINE, Cochrane Library, and Scopus databases was conducted according to the PRISMA guidelines (end-of-search date: July 8, 2020). The National Heart, Lung, and Blood Institute and Newcastle-Ottawa scales was utilized for quality assessment. RESULTS: Five studies reporting on 72 patients were included. The studies investigated the use of RRVP-assisted BAV in infants (> 1 mo) and older children, but not in neonates. Ten (13.9%) patients had a history of some type of aortic valve surgical or catheterization procedure. Before BAV, 58 (84.0%), 7 (10.1%), 4 (5.9%) patients had AR grade 0 (none), 1 (trivial), 2 (mild), respectively. After BAV, 34 (49.3%), 6 (8.7%), 26 (37.7%), 3 (4.3%), patients had AR grade 0, 1, 2, and 3 (moderate), respectively. No patient developed severe AR after RRVP. One (1.4%) developed ventricular fibrillation and was defibrillated successfully. No additional arrhythmias or complications occurred during RRVP. CONCLUSION: RRVP can be safely used to achieve balloon stability during pediatric BAV, which could potentially decrease AR rates.

Rapid right ventricular pacing for balloon aortic valvuloplasty: expanding its routine use in neonates and infants.

OBJECTIVE: Rapid right ventricular pacing during balloon aortic valvuloplasty is commonly used to achieve balloon stability in children and adults. There is no consensus for the use of the technique in neonates and infants. We sought to review our institutional experience with rapid right ventricular pacing-assisted balloon aortic valvuloplasty across all age groups and evaluate the safety and effectiveness of the technique in the sub-group of neonates and infants <12months. METHODS: Retrospective study between February, 2011 and February, 2020. RESULTS: A total of 37 patients (Group I: 21 neonates/infants <12months and Group II: 16 children 12 months-16 years) were analysed. Catheter-measured left ventricular to aortic gradient reduced from median of 66 mmHg (with a range from 30 to 125 mmHg) to 14 mmHg (with a range from 5 to 44 mmHg) in Group I and 44 mmHg (with a range from 28 to 93 mmHg) to 18 mmHg (with a range from 2 to 65 mmHg) in Group II (p < 0.001). Procedure and fluoroscopy times were identical in the two groups. Balloon:annulus ratio was 0.94 and 0.88 in Groups I and II, respectively. Freedom from reintervention was 100% for Group I at a median time of 3.2 years and 81% at 2.7 years for Group II. Reinterventions in Group II (3/16 pts) were performed predominantly for complex left ventricular outflow tract stenosis. At follow-up echocardiogram, 45% of patients in Group I had no aortic regurgitation, 30% trace-mild, 20% mild-moderate, and 5% moderate aortic regurgitation, whereas in Group II, 50% of patients had no aortic regurgitation, 32% had mild aortic regurgitation, and 18% mild-moderate aortic regurgitation. Unicuspid valves were only encountered in Group 1 (2/21 pts, 10%) and they were predictive of mild-aortic regurgitation during follow-up (p = 0.003). Ventricular fibrillation occurred in three neonates with suspicion of myocardial ischemia on the pre-procedure echocardiogram. All were successfully defibrillated. CONCLUSIONS: Rapid right ventricular pacing can be expanded in neonates and infants to potentially decrease the incidence of aortic regurgitation and reintervention rates, hence avoiding high-risk surgical bail-out procedures for severe aortic regurgitation in the first year of life. Myocardial ischemia may predispose to ventricular dysrhythmias during rapid right ventricular pacing.

Right Anterior Mini-Thoracotomy for Discrete Fibromembranous Subaortic Stenosis.

Discrete fibromembranous subaortic stenosis is a common type of subaortic stenosis causing clinically significant left ventricular outflow obstruction. Surgery for discrete subaortic stenosis is most often performed through a typical midline sternotomy. Herein, we present our experience with an adult patient who underwent a right mini-thoracotomy for subaortic membrane resection with central cannulation under direct operative vision.

The aberrant subclavian artery: approach to management.

PURPOSE OF REVIEW: Aberrant subclavian artery (ASCA) represents one of the most common congenital vascular anomalies of the aortic arch. The majority of ASCAs are associated with an aneurysm which occurs at their origin from the descending thoracic aorta, namely, the Kommerell's diverticulum. In this review, we discuss recent data with regards to indications of treatment and surgical management of these anatomical variants. RECENT FINDINGS: Various surgical methods have been described for the repair of ASCA and Kommerell's diverticulum. Traditionally, treatment included open surgery; however, recent studies describe a shift of conventional treatment to more hybrid or endovascular approaches. The heterogeneity in the anatomy and presentation of these clinical entities as well as patient-related factors have prevented conduction of randomized trials for the best available modality of treatment. This dearth of literature is well depicted in the current guidelines. SUMMARY: The optimal surgical procedure has to be tailored to every patient according to the presentation, individual anatomy, and patient's risk profile. Conventional surgery for ASCA and Kommerell's diverticulum has acceptable mortality and complication rates, whereas hybrid repairs report encouraging results. Further studies are required to provide sufficient evidence which will formulate a clear frame of treatment indications and optimal surgical methods, as well as evaluate long-term results following hybrid repair.

Levoatriocardinal Vein: A Rarely Recognized Cause of Recurrent Cardiac and Cerebral Thromboembolic Events.

Levoatriocardinal vein (LACV) is a rare congenital anomaly of the systemic veins. We describe the case of a 43-year-old patient who presented with a transient ischemic attack episode, desaturation, and ventricular arrhythmias. Transesophageal echocardiography diagnosed a patent foramen ovale, and magnetic resonance imaging revealed 2 small myocardial infarcts, despite normal coronaries on subsequent angiography. Echocardiography and cardiac computed tomography revealed an LACV with bidirectional flow. The patient underwent percutaneous LACV and patent foramen ovale closure, with immediate saturation increase after occlusion of the LACV. To the best of our knowledge, this is the first time an LACV is identified as the cause of recurrent thromboembolic events.

Situs Inversus Totalis: Single-Stage Anatomic Repair of Complex Congenital Heart Disease.

Transposition of the great arteries occurs rarely in patients with mirror image dextrocardia and situs inversus, while the combination with severe coarctation of the descending aorta (CoA) makes the anatomy even more unusual. Therefore, it is not surprising that a case with such unusual and complicated anatomy presents unique problems when a primary definitive correction is attempted. We report a patient with situs inversus totalis and complex congenital heart disease including transposition of the great arteries and severe CoA who underwent successful complete, single-stage, anatomic correction.

Pulmonary valve replacement in patients with corrected tetralogy of Fallot.

Introduction: Development of pulmonary insufficiency in patients with surgically corrected tetralogy of Fallot (TOF) may lead to severe right heart failure with serious consequences. We herein present our experience with pulmonary valve replacement (PVR) in these patients. Methods: From 2005-2013, 99 consecutive patients (71 males/28 females, mean age 38±8 years), underwent PVR after 7 to 40 (mean 29 ± 8) years from the initial correction. Seventy nine of the symptomatic patients presented in NYHA II, 14 in III and 2 in IV. All underwent PVR with a stented bioprosthetic valve, employing a beating heart technique with normothermic extracorporeal circulation support. Concomitant procedures included resection of aneurysmal outflow tract patches (n = 37), tricuspid valve annuloplasty (n = 36), augmentation of stenotic pulmonary arteries (n = 9), maze procedure (n = 2) and pulmonary artery stenting (n = 4). Results: There were 2 perioperative deaths (2%). One patient developed sternal dehiscence requiring rewiring. Median ICU and hospital stay was 1 and 7 days respectively. Postoperative echocardiography at 6 and 12 months showed excellent bioprosthetic valve performance, significant decrease in size of the right cardiac chambers and reduction of tricuspid regurgitation (TR) in the majority of the patients. At mean follow-up of 3.6 ± 2 years, all surviving patients remain in excellent clinical condition. Conclusion: Probability of reoperation for pulmonary insufficiency in patients with surgically corrected TOF increases with time and timely PVR by preventing the development of right heart failure is crucial for long-term survival. Current bioprosthetic valve technology in combination with the beating heart technique provides excellent immediate and short-term results. Further follow-up is necessary to evaluate long-term outcome.

Atrial mass: a myxoma?

A middle-aged woman with a history of resected colorectal cancer and receiving chemotherapy presented with a right atrial mass and the provisional diagnosis of myxoma supported by echocardiography, computed tomography, and magnetic resonance imaging. Successful surgical removal revealed organized thrombus instead. Atrial thrombus may be mistaken for myxoma and long-term intracardiac indwelling catheters can be thrombogenic.

Aorto-Right Ventricular Tunnel: An Uncommon Problem with a Common Solution.

Aorto-ventricular tunnel is a rare congenital malformation, and aorto-right ventricular tunnel (ARVT) is an even less common entity. Here, we report the case of a 3-month-old female who underwent successful surgical closure of ARVT. The origin of the right coronary artery was proximal to the ostium of the tunnel.

T-Bar Utilization for Concomitant Coronary Artery Bypass Graft Operation and Left Upper Lobectomy.

Management in patients with coexisting coronary artery disease and lung carcinoma is usually a two-stage operation, with the cardiac surgery procedure followed by pulmonary resection at a later time. Delayed tumor resection on the other hand may be detrimental. Off-pump coronary artery bypass grafting could facilitate concomitant lung resection at one stage via median sternotomy. T-bar retractor may be a useful tool in the surgical approach of this combined operation.