Left Coronary Cusp Research Articles

Silent severe aortic regurgitation due to blunt chest trauma: ignore it at your peril—a case report

Abstract Background Blunt chest trauma (BCT) presenting to the emergency department is common and may cause life-threatening cardiac complications. Whilst complications causing haemodynamic instability are generally detected promptly, others may present late with long-term consequences. We describe a rare, serious complication of BCT presenting five years after a road traffic accident (RTA). Case summary A 23-year-old man was incidentally found to have a murmur. Past history was notable only for BCT with rib fracture sustained in a RTA 5 years prior. Examination revealed a hyperdynamic pulse, loud decrescendo diastolic murmur, and Duroziez’s sign over the femoral arteries. Echocardiography showed severe valvular aortic regurgitation (AR) from a hole in the left coronary cusp and holodiastolic flow reversal in the descending aorta. The left ventricle (LV) showed marked dilatation in diastole, mild dilatation in systole, and preserved systolic function. The aorta was normal. Severe AR was attributed to his previous BCT, with AR causing subsequent LV dilatation. He underwent aortic valve replacement (AVR) with rapid recovery. He remains well, and his echo shows a well-functioning AVR with normalization of LV dimensions. Discussion Aortic regurgitation following BCT is rare but well-recognized, most often resulting from RTAs. Only a third of cases are diagnosed acutely. In others, lack of haemodynamic instability means that emergency echocardiography is not routinely performed, such that this may go unrecognized with long-term consequences. Clinicians should be aware of possible valve damage following BCT. Prompt echocardiography should be routinely performed for all BCT at initial presentation, even without haemodynamic instability.

Quadricuspid aortic valve and its rare association with left main obstruction: case report and literature review.

The quadricuspid aortic valve (QAV) is a rare congenital anomaly. We report a 51-year-old woman with QAV who experienced intermittent chest pain due to fibrotic tissue overgrowth from the small left coronary cusp, obstructing the left main coronary artery (LM). Angiography revealed a large "Vieussens' arterial ring," which acted as a collateral channel from the right coronary artery to the left coronary artery, preserving coronary blood flow and left ventricular function. Surgery successfully removed the tissue, maintaining both aortic valve function and coronary patency. This case highlights the need to consider QAV complications and use various imaging modalities for accurate diagnosis and treatment planning, including evaluating potential issues like aortic regurgitation and coronary anomalies.

Premature ventricular contraction arising from the left coronary sinus cusp: Which signal is the target of ablation?

We described a premature ventricular contraction arising from the left coronary sinus cusp, in which we discussed about the interpretations of the signals recorded there. Our case provided further insights into the interpretation of signals recorded at the coronary sinus cusp during premature ventricular contraction ablation.

Can the QRS morphology of outflow tract ventricular arrhythmia change when right bundle branch block emerges during sinus rhythm?

QRS morphology can change during ventricular arrhythmias (VAs) with the appearance of bundle branch block (BBB). We retrospectively investigated 195 consecutive patients who underwent an initial ablation of VA. The study inclusion criteria were VAs that were successfully ablated in the outflow tract (OT) and in whom right bundle branch block (RBBB) was induced by catheter manipulation close to the His bundle area during sinus rhythm, before any radiofrequency application. We analyzed the QRS morphology of the VAs with and without RBBB during sinus beats. Twenty-four patients (age 59±17 years, female 14) developed RBBB at some point during their procedure. The successful ablation sites of the VAs were the right ventricular outflow tract (RVOT) in 12 patients, pulmonary artery in one, left coronary cusp in five, right coronary cusp in three, right-left cusp junction in two, and great cardiac vein in two. QRS-morphology change was observed in five (20%) cases. The successful ablation sites in that group were the left coronary cusp in three cases, right coronary cusp in one, and RVOT septum in one. The QRS duration of the VAs increased during RBBB. There are some cases of OT-VAs in which the QRS waveform changes with the appearance of catheter induced RBBB. We need to be aware that when QRS morphology changes during an OT-VA ablation, it does not necessarily mean that the origin or exit of the VA has changed.

Surgical management of native aortic valve leaflet avulsion during TAVR

BackgroundTranscatheter aortic valve replacement (TAVR) has increased in utilization since its approval for management of aortic stenosis patients across all risk strata. We report a rare case of aortic valve leaflet avulsion after balloon expandable TAVR managed with urgent surgery.Case presentationA 78-year-old male underwent TAVR complicated by avulsion of the native aortic valve leaflet’s left coronary cusp. He was taken for urgent surgery for cusp resection to prevent thromboembolic complications.ConclusionsNative aortic valve leaflet avulsion should be suspected during TAVR in instances of extreme hemodynamic instability after balloon aortic valvuloplasty. As TAVR expands in lower risk patients, surgeons should have a low threshold to intervene surgically to treat native leaflet avulsion or other complications.

Electrophysiological and Clinical Characteristics of Premature Ventricular Contractions (PVCs) Originating From the Left Coronary Cusp (LCC) Versus Site 3 of the Right Ventricular Outflow Tract (RVOT)

Electrophysiological and Clinical Characteristics of Premature Ventricular Contractions (PVCs) Originating From the Left Coronary Cusp (LCC) Versus Site 3 of the Right Ventricular Outflow Tract (RVOT)

Clinical, Electrophysiological Characteristics and Long-Term Outcomes of Catheter Ablation of Premature Ventricular Contractions Originating From Left Coronary Cusp

Clinical, Electrophysiological Characteristics and Long-Term Outcomes of Catheter Ablation of Premature Ventricular Contractions Originating From Left Coronary Cusp

Acute occlusion of the left main coronary artery following impedance rise after high-frequency catheter ablation.

We present a case of catheter ablation of a premature ventricular complex complicated by left main injury. During ablation from the left coronary cusp, a sudden rise in impedance was followed by ST elevation on the ECG. Angioplasty and stenting were performed immediately; however, the stent subsequently developed repeated stenosis.

Impact of commissural versus coronary alignment on risk of coronary obstruction following transcatheter aortic valve implantation.

Transcatheter aortic valve implantation (TAVI) with commissural alignment aims to limit the risk of coronary occlusion and maintain good coronary access. However, due to coronary origin eccentricity within the coronary cusp, coronary-commissural overlap (CCO) may still occur. TAVI using coronary alignment, rather than commissural alignment, may further improve coronary access. To compare rates of CCO after TAVI using commissural versus coronary alignment methodology. Cardiac CT scans from 102 patients with severe (tricuspid) aortic stenosis referred for TAVI were analysed. Native cusp asymmetry and coronary eccentricity were defined and used to simulate TAVI using commissural versus coronary alignment. Rates of optimal coronary alignment (< 10° from cusp centre) and severe misalignment (< 15° from coronary-commissural overlap) were compared. Additionally, the impact of valve misalignment during implantation was assessed. The native right coronary artery (RCA) origin was 15.8° (9.5 to 24°) closer to the right coronary cusp/non-coronary cusp (RCC-NCC) commissure than the centre of the right coronary cusp. The native left coronary artery (LCA) origin was 4.5° (0 to 11.5°) closer to the left coronary cusp/non-coronary cusp (LCC-NCC) commissure than the centre of the left coronary cusp (p < 0.01). Compared to commissural alignment, coronary alignment doubled the proportion of optimally-aligned RCAs (62/102 [60.8%] vs. 31/102 [30.4%]; p < 0.001), without a significant change in optimal LCA alignment (62/102 [60.8% vs. 74/102 [72.6%]; p = 0.07). There were no cases of severe misalignment with either strategy. Simulating 15° of valve misalignment resulted in severe RCA compromise risk in 7/102 (6.9%) of commissural alignment cases, compared to none using coronary alignment. Fluoroscopic projection was similar with both approaches. Coronary alignment resulted in a 2-fold increase of optimal TAVI positioning relative to the RCA ostium when compared to commissural alignment without impacting the LCA. Use of coronary alignment rather than commissural alignment may improve coronary access after TAVI and is less sensitive to valve rotational error, particularly for the right coronary artery.

Imaging-derived tissue visualization guides catheter ablation of premature ventricular contractions

Abstract Background The presence of myocardial scarring is associated with worse outcomes after catheter ablation of premature ventricular contractions (PVCs). Three-dimensional substrate characterization is emerging for peri-procedural ablation guidance, but its value for tissue visualization during PVC ablation is unknown. Purpose The aim of the present study was to assess the impact of imaging-derived tissue visualization on lesion planning, procedural and clinical outcomes of PVC ablation. Methods Thirteen consecutive patients (92.3% male, 62.2±12.4 years) undergoing unipolar (n=8) or bipolar (n=5) PVC catheter ablation with integrated three-dimensional imaging from multidetector computed tomography or cardiac magnetic resonance imaging were included. All patients presented with assumed myocardial scarring due to an underlying cardiomyopathy and/or after previous ablation. Results Among all patients (30.8% (peri-)myocarditis, 20.0% ischemic, 15.4% dilated cardiomyopathy, 15.4% idiopathic, 7.7% nonischemic, 7.7% congenital heart disease) undergoing ablation of 20 PVC morphologies (median 1 (IQR 1-2) per patient; 75.0% non-outflow tract; 70.0% left-sided), myocardial scarring was present in 11/13 (84.6%). Wall thinning &amp;lt;5 mm covering an area of 36.1±17.8 cm² contained the PVC origin in 4/13 (30.8%) patients and was safely targeted with radiofrequency lesions with up to 45 W (maximum power: median 32 W (IQR 30-35)) (Figure 1). Imaging-guided bipolar ablation was performed in 5/8 (62.5%) patients with previously therapy-refractory PVCs including foci at the left ventricular summit and the right ventricular outflow tract each in 2 and the left coronary cusp in one patient (Figure 2). PVCs were efficiently suppressed with less radiofrequency lesions (5.4±3.8 vs. 55.8±36.9; p=0.0160) with shorter duration (4.1±3.2 min vs. 23.3±13.5 min; p=0.0152) compared to prior unipolar ablation. Bipolar lesions resulted in a higher impedance (158 Ω (IQR 101-174) vs. 106 Ω (IQR 99-124); p=0.0025), while requiring a lower temperature (36 °C (IQR 35-38) vs. 39 °C (IQR 36-43); p=0.0001) and less power (26 W (IQR 20-30) vs. 30 W (IQR 25-31); p=0.0376). Complete suppression of the clinical PVC was reached in all 13 patients. During a follow-up of 396.8±299.7 days, PVC burden decreased from 20.1±14.3% to 1.7±1.6% (p=0.0172). Conclusions Imaging-derived tissue visualization enables determination of myocardial wall thinning &amp;lt;5 mm as a substrate for recurrent PVCs, which can be safely targeted. Three-dimensional imaging efficiently guides high power lesion application and bipolar ablation of PVCs at anatomically challenging foci.Anatomically challenging fociImaging-guided bipolar ablation

Angulation and curvature of aortic landing zone affect implantation depth in transcatheter aortic valve implantation

In transcatheter aortic valve implantation (TAVI), final device position may be affected by device interaction with the whole aortic landing zone (LZ) extending to ascending aorta. We investigated the impact of aortic LZ curvature and angulation on TAVI implantation depth, comparing short-frame balloon-expanding (BE) and long-frame self-expanding (SE) devices. Patients (n = 202) treated with BE or SE devices were matched based on one-to-one propensity score. Primary endpoint was the mismatch between the intended (HPre) and the final (HPost) implantation depth. LZ curvature and angulation were calculated based on the aortic centerline trajectory available from pre-TAVI computed tomography. Total LZ curvature (kLZ,tot\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${k}_{LZ,tot}$$\\end{document}) and LZ angulation distal to aortic annulus (αLZ,Distal\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\alpha }_{LZ,Distal}$$\\end{document}) were greater in the SE compared to the BE group (P < 0.001 for both). In the BE group, HPost was significantly higher than HPre at both cusps (P < 0.001). In the SE group, HPost was significantly deeper than HPre only at the left coronary cusp (P = 0.013). At multivariate analysis, αLZ,Distal\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${\\alpha }_{LZ,Distal}$$\\end{document} was the only independent predictor (OR = 1.11, P = 0.002) of deeper final implantation depth with a cut-off value of 17.8°. Aortic LZ curvature and angulation significantly affected final TAVI implantation depth, especially in high stent-frame SE devices reporting, upon complete release, deeper implantation depth with respect to the intended one.

Contemporary Valvular Mechanisms of Aortic Regurgitation in Tricuspid Aortic Valves: Importance in Repair Versus Replacement Strategy.

This study was performed to determine cusp causes of aortic regurgitation in patients with tricuspid aortic valves without significant aortic dilatation and define cusp pathologies amenable to surgical repair (aortic valve repair [AVr]) versus aortic valve replacement. We retrospectively reviewed surgical reports of consecutive adults with tricuspid aortic valves undergoing surgery for clinically significant aortic regurgitation within a prospective registry from January 2005 to September 2019. Valvular mechanisms were determined by systematic invivo intraoperative quantification methods. Of 516 patients, 287 (56%) underwent repair (AVr; mean±SD age, 59.9±12.4 years; 81% men) and 229 (44%) underwent replacement (aortic valve replacement; mean±SD age, 62.8±13.8 years [P=0.01 compared to AVr]; 67% men). A single valvular mechanism was present in 454 patients (88%), with cusp prolapse (46%), retraction (24%), and perforation (18%) being the most common. Prolapse involved the right cusp in 86% of cases and was more frequent in men (P<0.001). Two-dimensional transesophageal echocardiography accuracy for predicting mechanisms was 73% to 82% for the right cusp, 55% to 61% for the noncoronary cusp, and 0% for the left-coronary cusp. Cusp prolapse, younger age, and larger patient size were associated with successful AVr (all P<0.03), whereas retraction, perforation, older age, and concomitant mitral repair were associated with aortic valve replacement (all P<0.03). Right cusp prolapse is the most frequent single valvular mechanism in patients with tricuspid aortic valve aortic regurgitation, followed by cusp retraction and perforation. The accuracy of 2-dimensional transesophageal echocardiography is limited for left and noncoronary cusp mechanistic assessment. Prolapse is associated with successful AVr, whereas retraction and perforation are associated with aortic valve replacement. With systematic intraoperative quantification methods and current surgical techniques, more than half of tricuspid aortic valve aortic regurgitation cases may be successfully repaired.

Focal atrial tachycardias originating from the aorta-mitral continuity: Anatomical and electrophysiological characteristics

BackgroundThe aorta-mitral annulus conjunction (AMC) is an uncommon site of origin of focal atrial tachycardias (ATs). Hence, the electrophysiological and ablation target characteristics are poorly described. ObjectiveThe purpose of this study was to describe the characteristics of AMC ATs in detail. MethodsThe study enrolled 650 patients with ATs, 21 (3.2%) of whom had ATs originating from the AMC. A comprehensive evaluation, including electrocardiography, electrophysiology study, computed tomography scan, and intracardiac echocardiography, was performed. ResultsThe majority (19, 90.5%) of ATs occurred spontaneously. The mean age of this group was 48.9 ± 21.6 years, with 12 being female (57.1%). Seventeen patients had a typical biphasic P wave with a prominent positive component. The earliest activation site in the right atrium was near the His bundle, with average activation −10.3 ± 6.0 ms preceding the P wave. The successful ablation targets were distributed as follows: 1 case at 9 o’clock, 6 cases at 10 o’clock, 7 cases at 11 o’clock, 6 cases at 12 o’clock, and 1 case in the left coronary cusp. The local AMC potential differed from the commonly perceived annular potential and was characterized by a prominent A wave and a smaller V wave (atrial-to-ventricular ratio > 1). The angle of encroachment on the left atrial anterior wall, compressed by the left coronary cusp, was significantly smaller in the AMC ATs group than in the control group consisted of 40 patients who underwent coronary artery CT scans because of the chest pain but without atrial arrhythmias were randomly selected, which may have contributed to the arrhythmia substrate (141.7° ± 11.5° vs 155.2° ± 13.9°; P = .026). ConclusionA new strategy for mapping AMC ATs has been introduced. The ablation target should have an atrial-to-ventricular ratio of >1.

ANOMALY OF ORIGIN AND COURSE OF THE CIRCUMFLEX ARTERY: AN ECHOCARDIOGRAPHIC DIAGNOSIS

ANOMALY OF ORIGIN AND COURSE OF THE CIRCUMFLEX ARTERY: AN ECHOCARDIOGRAPHIC DIAGNOSIS

Virtual Reality Computed Tomography Evaluation - Anatomy and Clinical Implications for Valve-Sparing Aortic Root Replacement.

Three-dimensional aortic root evaluation using virtual reality (VR) techniques for valve-sparing aortic root replacement (VSARR) preparation has not yet been implemented, so we demonstrated VR computed tomography (VR-CT) and assessed its utility for VSARR.Methods and Results: We enrolled 72 patients who underwent multidetector CT before elective VSARR for annuloaortic ectasia with tricuspid aortic valve. The geometries of their aortic roots were measured with a VR-CT workstation. The mean values of geometric height (GH), free margin length (FML), and commissural height (CH) were 17.2±2.4 mm, 36.0±5.2 mm, and 24.0±4.3 mm, respectively. The right coronary/noncoronary CH was significantly greater than the left coronary/right coronary and left coronary/noncoronary CH. The left coronary cusp had the shortest FML, intercommissural distances (ICD), and smallest central angle. Although the right coronary cusp had the largest values for FML, ICD, and central angle, the right coronary cusp had the lowest GH and EH. The VR-CT measurements strongly correlated with intraoperative alternatives, especially with mean GH (R2=0.75) and left coronary/noncoronary CH (R2=0.79). Furthermore, mean GH was observed to be significantly different among the selected graft size groups; therefore, the preoperative mean GH could play a significant role in graft sizing. VR-CT evaluation allows a thorough understanding of aortic root anatomy, which could facilitate VSAAR.

Mapping and ablation of ventricular arrhythmias arising from the left ventricular summit.

The left ventricular summit (LVS) refers to the highest portion of the left ventricular outflow tract (LVOT). It is an epicardially delimited triangular area by the left coronary arteries and the coronary venous circulation. Its deep myocardium correlates closely with the left coronary cusp, aortic-mitral continuity, and right ventricular outflow tract (RVOT), complicating the anatomical relationship. Ventricular arrhythmias (VAs) originating from this area are common, accounting for 14.5% of all VAs origin from left ventricle. Specific electrocardiogram (ECG) characteristics may assist in locating LVS-VAs pre-procedure and facilitate procedure planning. However, catheter ablation of LVS-VAs remains challenging because of anatomical constraints. This paper reviews the recent understanding of LVS anatomy, concludes ECG characteristics, and summarizes current mapping and ablation methods for LVS-VAs.

Case report: A case of an anomalous right coronary artery arising from the left coronary cusp.

Abstract&#x0D; An anomalous origin of the right coronary artery is usually asymptomatic. It is mostly found incidentally on an invasive diagnostic angiogram. It does lead to an increased risk of sudden cardiac death, especially in younger patients. We present a case of a 41-year-old who had presented to the hospital with complaints of chest pain. The patient was evaluated by cardiology who performed an angiography that identified an anomalous origin of the right coronary artery arising from the left coronary cusp but no evidence of coronary artery disease. Once identified, these anomalous vessels should be corrected surgically, as these conditions increase the risk of sudden cardiac death arrhythmia and ischemic events.&#x0D; &#x0D; INTRODUCTION&#x0D; Anomalous aortic origin of the right coronary artery (AAORCA) is an uncommon congenital malformation with varying clinical presentations ranging from asymptomatic to sudden cardiac death (SCD). Those with symptoms or high-risk lesions are usually managed by unroofing or reimplantation, coronary artery bypass graft (CABG), AAORCA treated with right internal memory artery graft with proximal RCA ligation.&#x0D; &#x0D; CASE DESCRIPTION&#x0D; A 41-year-old female patient with obesity and hypertension presented with a 1-year history of intermittent exertional substernal pressure radiating to left shoulder and back. The pain, which lasted about 10 minutes per episode, had been more frequent and intense over the past week.Upon initial evaluation, she was hypertensive at 150/90 mmHg and heart rate 60 bpm. Blood work was unremarkable, including negative serial troponin levels. Electrocardiography showed sinus bradycardia without ischaemic changes. Anomalous origin of RCA was incidentally discovered from computed tomography (CT) of the chest. Coronary angiography and ascending aortography were then performed, which revealed a patent RCA originating from the left coronary cusp (Fig. 1A). CT heart angiography with reconstruction revealed the RCA ostium in the left coronary cusp with a malignant course between the aorta and pulmonary artery and without an obvious intramural segment&#x0D; Discussion:&#x0D; &#x0D; An anomalous origin of the right coronary artery (RCA) is a rare congenital anomaly that was first described in 1948 by White and Edwards. After carrying out angiography in 126,595 patients, Yamanaka and Hobbs reported the incidence of anomalous origin of the right and left coronary arteries as 136 (0.107%) and 22 (0.017%), respectively. The prevalence of an anomalous origin of RCA (ARCA) arising from the left coronary cusp with an inter-arterial course varies between 0.026% and 0.25%. An ARCA is more common than the anomalous origin of the left coronary artery (ALCA), but the latter is shown to be responsible for up to 85% of sudden cardiac deaths (SCD) related to the anomalous origins of arteries. Most coronary anomalies are detected incidentally on diagnostic angiography and are clinically insignificant; some, however, have been associated with an increased risk of SCD. It is second only to hypertrophic cardiomyopathy as a leading cause of SCD in young athletes. Mechanical compression of the RCA by the great vessels, which dilate and compress the RCA during periods of increased stroke volume, is the usual explanation for coronary ischemia. Patients usually have no ischemic changes on an electrocardiogram (ECG) at rest; however, multi-detector computed tomography (MDCT) is being used to evaluate the course of anomalous vessels outlying their relative positions to the aorta and the pulmonary artery. It also gives additional information regarding any stenotic lesion in these anomalous vessels. Echocardiography (Echo), magnetic resonance angiography (MRA), MCDT, and cardiac catheterization are all complementary diagnostic tools for evaluating anomalous coronary arteries [10]. While it is agreed that surgical correction is the standard of care for ALCA, when found, the management for right ARCA is more complicated. Treatment options for these patients include observation with medical therapy, percutaneous intervention (stenting), or surgery. Early diagnosis of coronary artery anomalies based on the patients’ symptoms can help decrease the incidence of sudden cardiac deaths, fatal arrhythmias, and ischemic events in the high-risk population.&#x0D; &#x0D; Conclusions &#x0D; &#x0D; Coronary anomalies should be suspected in symptomatic young patients with a normal cardiac workup. Non-invasive imaging modalities such as a CTCA can help establish the diagnosis

Comparative Analysis of Morphological and Morphometric Features of Human, Pig, Calf, and Sheep Aortic Valves: A Cross-sectional Study

Introduction: The aortic valve plays a critical role in maintaining unidirectional blood flow from the left ventricle into the aorta, ensuring efficient circulation throughout the body. Comprising three cusps-the left coronary, right coronary, and non-coronary cusps-the intricate anatomy of the aortic valve is essential for its proper function. The scarcity of aortic valve homografts for transplantation has led to increased interest in studying readily available sources for suitable and durable xenografts. Aim: To compare the morphological and morphometric characteristics of the aortic valves in humans with those in pigs, calves, and sheep. Materials and Methods: The present cross-sectional study was conducted over a three-week period in July 2022. Aortic valves were collected from humans, pigs, calves, and sheep. Five human hearts were obtained from the Anatomy Department of Adichunchanagiri Institute of Medical Sciences, BG Nagar. Additionally, five hearts each from calves, pigs, and sheep were obtained from a nearby abattoir. The hearts were then fixed in a 10% formaldehyde solution for approximately 18 hours. All fat and muscle surrounding the aorta were removed, and the aorta with intact valves was dissected. An incision was made between the left coronary and non-coronary aortic cusps to measure the individual cusps. Morphological and morphometric measurements, including annulus diameter, cusp height, commissural distances, and length of the lunula, were taken using a vernier calliper. The obtained values were statistically compared using paired t-test. Results: The mean values of various measurements of human aortic valves were found to be similar to those of pig aortic valves. Both humans and pigs have three aortic cusps, namely the left, right, and non-coronary cusps. The mean diameter of the aortic annulus in humans was 2.18 cm, while in pigs it was 2.28 cm. The height of the left and right cusps in both human and pig aortic valves was approximately 1.6 cm, whereas the height of the non-coronary cusp was 1.64 cm in humans and 1.38 cm in pigs. The external inter-commissural distance of the left cusp was 2.48 cm, and that of the right cusp was 2.58 cm in both humans and pigs. The external inter-commissural distance of the non-coronary cusp was 2.4 cm in humans and 2.36 cm in pigs. The length of the lunula and internal inter-commissural length of the aortic cusps in humans were relatively similar to those in pigs. However, when compared to measurements in cows and sheep, significant variations were observed. Conclusion: The study findings provide valuable insights into the potential suitability of pig aortic valves for xenograft transplantation and their implications for cardiac surgical procedures.

Congenital Hypoplastic Left Coronary Cusp.

Congenital Hypoplastic Left Coronary Cusp.

Impact of implantation depth and calcium burden on infranodal conduction delay after transcatheter aortic valve replacement

Infranodal conduction disorders are common after transcatheter aortic valve replacement (TAVR). Risk factors are incompletely understood. The purpose of this study was to assess the impact of valve implantation depth and calcium burden of the device landing zone on infranodal conduction intraprocedure pre- and post-TAVR. In all patients undergoing TAVR between June 2020 and June 2021, the His-ventricle (HV) interval was measured pre- and post-valve deployment. The difference between the 2 measurements defined delta HV, whereas infranodal conduction delay was defined as HV interval >55 ms. Valve implantation depth was measured as the distance between the aortic annular plane and the ventricular prosthesis end. Calcium burden was quantified as the volume of calcium in 6 regions of interest: the non-, right, and left coronary cusps (NCC, RCC, and LCC, respectively) and the corresponding regions of the left ventricular outflow tract (LVOT) underlying each cusp (LVOTNCC, LVOTRCC, LVOTLCC, respectively). Of 101 patients (mean age 81 ± 5.7 years; 47% women), 37 demonstrated infranodal conduction delay intraprocedure post-TAVR. Overall, mean implantation depth was 5 ± 3.1 mm, median calcium volume was 2080 mm3 [interquartile range 632-2400]. Delta HV showed no correlation with implantation depth or calcium burden (r = -0.08 and r = 0.12, respectively). However, LVOTNCC calcification was a significant predictor for infranodal conduction delay post-valve deployment in a multivariable logistic regression model (odds ratio 1.62 per 100-mm3 increase (95% confidence interval 1.06-2.69; P = .04). Assessment of LVOTNCC calcification may identify patients at risk for infranodal conduction delay after TAVR, whereas implantation depth did not predict infranodal conduction delay.