Left Ventricular Outflow Tract Pressure Research Articles

Follow-Up Study of Percutaneous Intramyocardial Septal Radiofrequency Ablation in the Treatment of Hypertrophic Obstructive Cardiomyopathy With HFpEF.

The study aimed to evaluate the changes of left ventricular diastolic function and the improvement of clinical symptoms in hypertrophic cardiomyopathy (HCM) patients with heart failure with preserved ejection fraction (HFpEF) after percutaneous intramyocardial septal radiofrequency ablation (PIMSRA). This study enrolled 31 adult HCM patients with HFpEF who underwent PIMSRA treatment. Electrocardiogram, imaging, and blood biochemical examinations were performed on these patients during a 6-month follow-up. Compared with the baseline, at 6 months after PIMSRA, patients showed significant reductions in peak left ventricular outflow tract pressure gradients (resting gradient: from a mean of 83.24 to 23.40mmHg, p < 0.001; postexercise gradient: from a mean of 109.70 to 33.39mmHg, p< 0.001). The interventricular septal thickness reduced from a mean of 22.90 to 17.48mm, p < 0.001. The E/e' decreased from a median of 18.67 to 11.54, p < 0.001. The 6-minute walk distance (6MWD) increased from a mean of 359.03 to 435.81 m, p < 0.001. The Kansas City Cardiomyopathy Questionnaire Overall Summary Score (KCCQ OS) increased from a mean of 57.57 to 71.93, p < 0.001. The number of HFpEF patients diagnosed according to the European Society of Cardiology's Heart Failure Association HFA-PEFF score decreased from 31 to 23. None of the patients had new-onset bundle branch block or complete heart block after PIMSRA. PIMSRA is a safe and effective treatment. It can improve left ventricular diastolic function and quality of life in HCM patients.

Usefulness of exercise stress echocardiography for predicting cardiovascular events and atrial fibrillation in hypertrophic cardiomyopathy

BackgroundIn hypertrophic cardiomyopathy (HCM), the determinants of exercise tolerance and the usefulness of exercise stress echocardiography (ESE) for predicting hard endpoints have not been fully investigated. We aimed to assess the key parameters of ESE for exercise tolerance and the factors predictive of cardiovascular events and new-onset atrial fibrillation (AF) in patients with HCM. MethodsSeventy-four consecutive patients with HCM who underwent ESE and with an ejection fraction ≥50 % were enrolled. The primary endpoint was a composite of cardiovascular death, heart failure hospitalization, ventricular fibrillation or tachycardia, and ventricular assist device implantation. The secondary endpoint was new-onset AF. ResultsThe primary endpoint occurred in 13 patients. The left and right ventricular functions during exercise were responsible for decreased exercise tolerance. Peak exercise e′ and tricuspid annular plane systolic excursion (TAPSE) significantly predicted increased primary outcome risk (hazard ratio 1.35, 95 % confidence interval 1.10–1.76, p = 0.003; hazard ratio 1.19, 95 % confidence interval 1.07–1.32, p = 0.002, respectively), and the results were consistent even after adjustment by maximum workload. These ESE parameters improved the prognostic model containing estimated glomerular filtration rate (eGFR) and left atrial (LA) volume index. In AF-naive patients (n = 58), LA volume, peak exercise LA reservoir strain, and left ventricular outflow tract (LVOT) pressure gradient predicted new-onset AF. ConclusionsIn patients with HCM, ESE parameters related to left and right ventricular function were responsible for low exercise tolerance. Furthermore, e′ and TAPSE at peak workload could be useful for predicting cardiovascular events in addition to eGFR and LA volume index. LVOT pressure gradient and LA function during exercise predicted new-onset AF.

Simultaneous alcohol septal ablation and intravascular imaging-guided percutaneous transluminal coronary angioplasty – An effective approach in patients with hypertrophic obstructive cardiomyopathy and critical coronary artery disease

Abstract We report a case of symptomatic hypertrophic obstructive cardiomyopathy refractory to medical management with a left ventricular outflow tract pressure gradient (LVOTPG) of 160 mmHg associated with a significant calcific coronary artery disease treated using simultaneous percutaneous transluminal septal myocardial ablation (PTSMA) and an intravascular imaging-guided percutaneous transluminal coronary angioplasty. The left anterior descending artery stenosis distal to the third septal perforator was stented using a drug-eluting stent under optical coherence tomography guidance. Subsequently, the LVOTPG was addressed using PTMSA. Following the procedure, the patient had an uncomplicated recovery. A follow-up echo revealed an LVOTPG of 15 mmHg 4 weeks later.

Association between Hypertrophic Cardiomyopathy and Variations in Sarcomere Gene and Calcium Channel Gene in Adults

Introduction: Calcium channel gene variations have been reported to be associated with hypertrophic cardiomyopathy (HCM) in family, but the relationship between calcium channel gene variations and HCM remains undefined in the population. Methods: A total of 719 HCM unrelated patients were initially enrolled. Finally, 371 patients were identified based on inclusion and exclusion criteria, including 145 patients with gene negative, 28 patients with a single rare calcium channel gene variation (calcium gene variation), 162 patients with a single pathogenic/likely pathogenic sarcomere gene variation (sarcomere gene variation) and 36 patients with a single pathogenic/likely pathogenic sarcomere gene variation and a single rare calcium channel gene variation (double gene variations). Then the demographic, electrocardiographic, echocardiographic, and follow-up data were collected. Results: Patients with double gene variations were at an earlier age and had more percent of family history of HCM, and had thicker walls, higher left ventricular outflow tract pressure gradient, more pathological Q waves, and more bundle branch blocks as compared with those with single sarcomere gene variation. During the follow-up period, patients with double gene variations had more primary endpoints than the other three groups (p = 0.0013). Multivariate analysis showed that double gene variations were the independent predictor of primary endpoint events in patients (HR: 4.82, 95% CI: 1.77–13.2; p = 0.002). Conclusion: We found that patients with double gene variations had more severe HCM phenotype and prognosis. The pathogenesis effects of sarcomere gene variation and calcium channel gene variation may be cumulative in HCM populations.

Individualised surgical treatment strategy for subaortic stenosis.

The clinical data of patients with subaortic stenosis who underwent surgical treatment in our centre in the past 12 years were reviewed. The short-term and long-term clinical outcomes were analyzed, and the long-term outcomes of different surgical methods for subaortic stenosis were compared to determine the optimal surgical treatment strategy for subaortic stenosis. From December 2010 to December 2022, 90 patients undergoing surgical treatment for subaortic stenosis in our hospital were enrolled. There were 55 males and 35 females with a median age of 72 (46,132) months and an average surgical weight of (21.35 ± 15.84) kg. According to the operation method, 90 patients were divided into group A (50 patients with simple subaortic membrane resection) and group B (40 patients with subaortic membrane and muscle resection or modified Konno procedure). There were three early deaths (3.33%). One late death occurred in group B. There was no significant difference in long-term survival rate between the two groups (p = 0.904). The preoperative left ventricular outflow tract pressure gradient in group B was (91.56 ± 36.98) mm Hg, which was higher than that in group A(51.13 ± 36.04)mm Hg(p < 0.001). There was no significant difference in immediate postoperative left ventricular outflow tract pressure gradient between group B [(5.44 ± 8.43) mm Hg] and group A [(7.82 ± 13.44) mm Hg] (p = 0.343). In the long-term follow-up, left ventricular outflow tract pressure gradient in group B was (5.86 ± 9.53) mm Hg, which was not statistically significant compared with group A (8.83 ± 14.52) mm Hg (p = 0.294). Eleven patients with moderate or greater aortic regurgitation (group A/group B: 3/8) underwent simultaneous aortic valvuloplasty. In group B, moderate or greater aortic regurgitation was significantly improved immediately after operation (p = 0.013) and was not significantly aggravated in long-term follow-up (p = 0.083), and there was no significant improvement in group A after operation and long-term follow-up. According to the different anatomical lesions of left ventricular outflow tract, the individualised surgical treatment strategy for patients with subaortic stenosis can achieve good long-term outcomes. The long-term survival rate and freedom from reoperation due to late left ventricular outflow tract obstruction after simple subaortic membrane resection and extended left ventricular outflow tract resection are comparable. For patients with moderate or greater aortic regurgitation before extended left ventricular outflow tract resection, simultaneous aortic valvuloplasty is beneficial to improve postoperative aortic valve function.

Individual Approach to Prescribing Sodium-Glucose Co-Transporter 2 Inhibitors in Patients with Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is a common hereditary disease of the myocardium. Sodium-glucose co-transporter 2 inhibitors are recognized as first-line drugs for the treatment of heart failure, but at the moment there is little known about their use in HCM.&#x0D; The aim. To assess the possibility of using an acute test with empagliflozin in patients with HCM with echocardiographic assessment of left ventricular outflow tract (LVOT) obstruction.&#x0D; Materials and methods. Twenty-six non-obstructive HCM patients were examined. All the patients underwent an acute test with sodium-glucose co-transporter 2 inhibitor using 10 mg of empagliflozin and echocardiographic examination before and 3 hours after administration. Twenty-four patients were included in the further analysis (2 patients were excluded due to arrhythmia). The patients were divided into two groups: group 1 included subjects with an increase in LVOT pressure after empagliflozin (12 patients), group 2 included those without an increase in the gradient (12 patients).&#x0D; Results. During the acute test, an increase in LVOT gradient occurred in 12 patients, and in 6 patients the gradient increased significantly and reached more than 30 mm Hg. The indicator at rest in patients before the test was 11.2 (10.1-19), after the test it was 12.45 (8.9-17) mm Hg (p = 0.042). The indicator at the height of the Valsalva test also increased from 15 (11-29) to 15.45 (10.4-33) mm Hg (p=0.29). Comparative analysis of clinical and echocardiographic data did not show significant difference between the groups.&#x0D; Conclusions. In some patients with HCM without signs of overt or latent obstruction at the baseline, a significant increase in LVOT pressure was noted after acute test with empagliflozin. Conducting an acute test in patients with HCM is appropriate to determine the possibility of the development of LVOT obstruction while taking the drug.

Comparative Evaluation of Alcohol Septal Ablation: Left Anterior Descending Versus Non-left Anterior Descending Artery Approaches

Alcohol septal ablation (ASA) is performed for symptomatic drug-refractory hypertrophic obstructive cardiomyopathy to reduce the left ventricular outflow tract pressure gradient (LVOTPG) by injecting ethanol into a septal branch that perforates the septal bulge. The target septal branches usually arise directly from the left anterior descending (LAD) artery; however, vessels from a non-LAD artery can be selected in some cases. This study aimed to compare effectiveness and safety between ASA performed using a septal branch arising from a non-LAD artery and a branch arising from the LAD artery. This single-center, retrospective, observational cohort study comprised patients with hypertrophic obstructive cardiomyopathy who underwent ASA at the Gifu Heart Centre between 2011 and 2022. The effectiveness and safety of ASA using the 2 artery types were compared. The primary endpoints were LVOTPG and procedure success, determined as LVOTPG <30 mmHg after 1 year. Of 33 patients (mean age: 66.4 ± 13.0 years; 13 males), 18 patients who underwent ASA using only LAD branches and 15 patients who underwent ASA using only non-LAD branches demonstrated no significant difference in the decrease in LVOTPG during the follow-up period (−99.1 ± 47.4 mmHg/year vs. −75.7 ± 39.2 mmHg/year, respectively, P = 0.19). The procedure success at 1 year was not significantly different between the 2 groups (93.3% and 84.6%, respectively, P = 0.58). ASA performed using septal branches from non-LAD arteries could be an alternative treatment approach when appropriate septal branches are missing or desirable effects cannot be obtained from ASA using LAD branches.

Effect of metoprolol in hypertrophic obstructive cardiomyopathy patients after alcohol septal ablation

BackgroundThe use of beta-blockers in hypertrophic obstructive cardiomyopathy (HOCM) patients after alcohol septal ablation (ASA) lacks data support. We aimed to evaluate the effect of metoprolol on exercise capacity, hemodynamic and laboratory parameters, and quality of life in HOCM patients after ASA. MethodsThis was a prospective randomized single-center open-label crossover trial in 21 HOCM patients after ASA. Patients received metoprolol and no beta-blocker for two periods of three months. The endpoints were: peak oxygen uptake (pVO2), maximal left ventricular outflow tract (LVOT) pressure gradient at peak exercise, a ratio of mitral peak velocity of the early filling (E) to early diastolic mitral annular velocity (e′) (E/e′) at rest, Kansas City Cardiomyopathy Questionnaire (KCCQ) overall summary score, and N-terminal prohormone of brain natriuretic peptide (NT-proBNP) plasmatic concentration. ResultsNo significant association was found between the treatment and any of the endpoints in the assessed patients: 1) pVO2 (19.5 ± 5.3 ml/kg/min vs. 19.4 ± 4.1 ml/kg/min, p = 0.90), 2) exercise-induced pressure gradient in LVOT 32 ± 37 mmHg vs. 32 ± 30 mmHg, p = 0.84, 3) E/e′ ratio at rest (11 ± 4 vs. 10 ± 4, p = 0.23), 4) KCCQ overall summary score (78 ± 11 vs. 77 te ± 15, p = 0.56), 5) NT-proBNP (215 pg/ml [121–333] vs. 153 pg/ml [102–228], p = 0.19). ConclusionsIn HOCM patients after successful ASA, metoprolol treatment did not improve exercise capacity, hemodynamic and laboratory parameters, or quality of life.

Alcohol septal ablation versus surgical septal myectomy of obstructive hypertrophic cardiomyopathy: systematic review and meta-analysis.

To elucidate the optimal septal reduction therapy for obstructive hypertrophic cardiomyopathy, we conducted a meta-analysis comparing alcohol septal ablation (ASA) and septal myectomy. MEDLINE, EMBASE and Cochrane CENTRAL were searched to identify studies investigating the outcomes of ASA and septal myectomy in patients with obstructive hypertrophic cardiomyopathy in January 2023. The primary outcome of interest was all-cause mortality in studies with ≥1 year of follow-up. The secondary outcomes of interest comprised left ventricular outflow tract (LVOT) pressure gradient reduction and reoperations of LVOT. A subgroup analysis of all-cause mortality including studies with follow-up ≥5 years was performed. 27 observational studies were included (15 968 patients). Analysis demonstrated similar all-cause mortality [hazard ratio (HR) (95% confidence interval) (CI) 1.24 (0.88-1.76); P = 0.21; I2 = 56%]. In contrast, ASA was associated with less reduction of LVOT pressure gradient and a reoperation rate [weighted mean difference (95% CI) 11.04 mmHg (5.60-16.48); P < 0.01; I2 = 64%, HR (95% CI) 9.14 (6.55-12.75); P < 0.001; I2 = 0%, respectively]. The subgroup analysis with follow-up ≥5 years revealed higher long-term mortality with ASA [HR (95% CI) 1.50 (1.04-2.15); P = 0.03; I2 = 52%]. Although both septal reduction therapies were associated with similar all-cause mortality, ASA was associated with a higher rate of reoperation and less reduction of LVOT pressure gradient. Furthermore, all-cause mortality with follow-up ≥5 years showed favourable outcomes with septal myectomy, although the result is only hypothesis-generating given a subgroup analysis.

Long-term outcomes and risk factors for mortality of patients with hypertrophic obstructive cardiomyopathy undergoing septal myectomy.

We aimed to evaluate the long-term surgical outcomes of patients with hypertrophic obstructive cardiomyopathy and explore the risk factors for mortality, especially those related to atrial fibrillation. We retrospectively reviewed 150 consecutive patients with hypertrophic obstructive cardiomyopathy who underwent surgical treatment between March 2003 and December 2020. Fifty (33.3%, age 53.7±16.1 years) patients underwent isolated septal myectomy (SM), 79 (52.7%, age 52.3±12.6 years) underwent SM with mitral valve intervention (SM + MVI), and 21 (14.0%, age 57.1±13.5 years) underwent SM with mitral valve replacement (SM + MVR). Overall peak left ventricular outflow tract pressure gradient at rest was significantly decreased from 91.9±43.2 to 13.3±13.0 mmHg (P<0.0001). Survival rates were 96.7%, 89.1%, and 81.5% at 30 days, 5 years, and 10 years, respectively. Patients in the SM + MVI group survived longer than those in SM + MVR or isolated SM groups (94.1% vs. 75.4% vs. 88.0%, respectively, at 5 years, P=0.05). Patients with preoperative atrial fibrillation had a worse 5-year survival rate than those without atrial fibrillation (73.4% vs. 92.8%, respectively, P<0.001). Preoperative atrial fibrillation was an independent risk factor for late mortality in multivariable analysis. Notably, those whose atrial fibrillation was successfully eradicated by surgical ablation had a better 5-year survival rate than other patients (87.7% vs. 28.6%, respectively, P<0.001). Surgical outcomes in hypertrophic obstructive cardiomyopathy are favorable in the long-term, except in patients with preoperative atrial fibrillation. Therefore, intraoperative ablation for preoperative atrial fibrillation in hypertrophic obstructive cardiomyopathy should be actively considered to improve patient outcomes.

Left ventricular remodeling following septal myectomy in hypertrophic obstructive cardiomyopathy

ObjectivesThe purpose of this study is to determine whether or not left ventricular remodeling can be induced after septal myectomy in patients with obstructive hypertrophic cardiomyopathy, and if so, how it occurs, using gated cardiac computed tomography. MethodsFifty patients with hypertrophic obstructive cardiomyopathy who underwent septal myectomy along the septal band between March 2016 and July 2020 were retrospectively reviewed. Recent consecutive 19 patients underwent postoperative cardiac computed tomography. In these patients, volumes of the septal band and thickness of 17 left ventricular myocardial segments were measured to determine the changes after surgery. ResultsThe resection volume predicted by preoperative computed tomography and the actual resection volume were 6.7 ± 3.3 mL and 6.4 ± 2.7 mL. In-hospital mortality was 0%. Moderate or greater mitral valve regurgitation and systolic anterior motion decreased from 56% to 6% and 86% to 6%, respectively. Median preoperative ventricular septal thickness and left ventricular outflow tract pressure gradient at rest decreased from 20.0 mm (interquartile range, 17.0-24.0 mm) and 74.0 mm Hg (interquartile range, 42.5-92.5 mm Hg) to 14.0 mm (interquartile range, 11.5-16.0 mm) and 15.5 mm Hg (interquartile range, 12.1-21.5 mm Hg), respectively. Postoperative computed tomography confirmed a reduction in septal band volume of 5.7 ± 2.8 mL. Total left ventricular myocardial volume was reduced by 12.9 ± 8.8 mL, which exceeded the volume reduction of the resected septal band. All segments except the basal inferior and basal inferolateral regions showed a significant decrease in wall thickness by a median of 6.4%. ConclusionsProperly performed septal myectomy may induce remodeling of the entire left ventricle, not just the resected area.

Real-world clinical outcomes of percutaneous transluminal septal myocardial ablation for patients with drug-refractory hypertrophic obstructive cardiomyopathy: results from a retrospective multicenter registry of non-high-volume centers.

Percutaneous transluminal septal myocardial ablation (PTSMA) is a well-established interventional therapy for drug-refractory hypertrophic obstructive cardiomyopathy (HOCM) as an alternative to surgical myectomy. Although guidelines recommend that PTSMA should be performed in institutions with extensive experience, it is not centralized to such high-volume centers in real-world clinical practice. Thus, this study aimed to assess the feasibility of PTSMA in non-high-volume centers. We retrospectively examined patients with HOCM who underwent PTSMA between August 2012 and May 2020 at four institutions that experienced fewer than 20 cases of PTSMA procedures. The primary clinical endpoint was a composite of safety (all-cause death, electrical defibrillation for ventricular tachycardia or fibrillation, cardiac tamponade, permanent pacemaker implantation, and repeated interventions) and efficacyendpoints (repeated interventions [PTSMA or surgical myectomy]). Fifty-eight consecutive patients were enrolled. During the 30-day follow-up, no major clinical adverse events were noted except three patients (5.2%) requiring permanent pacemaker implantation for complete atrioventricular block. The percentage of patients with New York Heart Association functional class 1 or 2 significantly increased from 8.6 to 100% (p < 0.001). In the Cox proportional hazard model, left ventricular outflow tract pressure gradient at rest ≥ 30mmHg (hazard ratio [HR] 6.56; 95% confidence interval [CI] 1.44-29.90; p = 0.015) and mitral regurgitation grade ≥ 3 (HR 10.75; 95% CI 1.81-63.79; p = 0.009) at the 30-day follow-up were associated with a composite of major clinical adverse events. The current study demonstrated that 58 patients who underwent PTSMA in non-high-volume centers had favorable 30-day clinical outcomes, with a primary composite endpoint rate of 5.2%. A prospective study with a larger sample size and longer follow-up is warranted to verify the safety and efficacy of PTSMA in non-high-volume centers.

Thoracoscopic Trans-mitral Septal Myectomy for Hypertrophic Obstructive Cardiomyopathy in the Elderly

BackgroundThe thoracoscopic trans-mitral approach can not only facilitate exposure of the ventricular septum, mitral valve, and subvalvular apparatus, it also enables the surgeons to perform concomitant mitral valve intervention. This study aimed to determine the safety and efficacy of thoracoscopic trans-mitral septal myectomy in elderly patients with hypertrophic obstructive cardiomyopathy (HOCM).MethodsWe reviewed the demographic to clinical characteristics and outcomes of patients who underwent thoracoscopic trans-mitral septal myectomy in our center between April 2019 and April 2021. The population was divided into a younger group (<60 years) and an elderly group (≥60 years).ResultsThere were 46 and 20 patients in the younger and elderly groups, respectively. The majority of patients in the elderly group were female (39.1 vs. 80.0%, P < 0.01). Patients in the elderly group were more likely to be in New York Heart Association Class IV (2.2 vs. 80.0%, P < 0.01). The European System for Cardiac Operation Risk Evaluation II predicted mortality rates were significantly higher (3.97 ± 1.81 vs. 1.62 ± 0.86%, P < 0.01) in the elderly group. In the elderly group, a patient converted to median sternotomy due to left ventricular posterior free wall rupture following septal myectomy and mitral bioprosthetic valve replacement. The patient then underwent double-patch sandwich repair for rupture and mitral mechanical valve replacement and was eventually discharged. All patients in the elderly group were discharged, while one in the younger group died. No patient in the elderly group required permanent pacemaker implantation vs. one in the younger group. Patients in the elderly group were more likely to spend more time in the intensive care unit than those in the younger group (5.44 ± 5.80 days vs. 3.07 ± 2.72, P < 0.05). However, there was no significant intergroup difference in in-hospital mortality or complications. Importantly, the left ventricular outflow tract pressure gradient was significantly decreased from 96.15 ± 32.89 mmHg to 8.2 ± 3.42 mmHg with no residual obstruction in the elderly group. The interventricular septal thickness was significantly decreased from 19.73 ± 3.14 mm to 11.30 ± 2.23 mm. Postoperative mitral regurgitation severity was significantly improved in the elderly group.ConclusionThis study demonstrated that thoracoscopic trans-mitral septal myectomy is a feasible option for selected elderly patients with satisfactory outcomes similar to those of young patients.

Left Atrial Strain is an Independent Determinant of Exercise Capacity in Hypertrophic Cardiomyopathy

Aims: The objective was to evaluate the potential contribution of left atrial (LA) function to reduced exercise capacity in patients with hypertrophic cardiomyopathy (HCM).Methods and results: Using a case-control design we randomly selected 95 patients with confirmed HCM based on guidelines criteria and without permanent atrial arrhythmia who underwent a treadmill exercise test. We measured echo-based left ventricular (LV) and LA morphology and function including mechanics using 2D speckle tracking. Preserved exercise capacity was defined as the 25 th percentile of metabolic equivalents (METs) or > 7 METs. Of 95 HCM patients, 36 had reduced exercise capacity (£7 METs) and 59 had preserved exercise capacity (>7 METs). Reduced exercise capacity patients were more likely to be older, female, had higher BMI, and more advanced heart failure symptoms. They also had a higher E/e’ ratio and lower LA reservoir and conduit strain but similar left ventricular outflow tract (LVOT) pressure gradients. By univariate analysis, LA reservoir and conduit strain, age, gender, BMI, NYHA class, and E/e’ correlated with METs. In multivariate analysis, LA conduit strain independently determined METs after adjusting for age, gender, BMI, NYHA and E/e’ (standardized coefficients 0.17, P=0.04). This relationship was primarily noted in non- and labile-obstructive but not in obstructive HCM. History of atrial fibrillation did not impact the association of LA strain with exercise capacity.Conclusion : Even after adjusting for LVOT gradients and diastolic function, reduced LA conduit strain is an independent determinant of exercise tolerance in HCM.

Sleep Disordered Breathing and Mortality in Patients With Hypertrophic Obstructive Cardiomyopathy Undergoing Septal Myectomy

ObjectiveTo determine the impact of sleep-disordered breathing (SDB) on survival in patients with hypertrophic cardiomyopathy (HCM) following septal myectomy. Patients and MethodsPatients with obstructive HCM undergoing septal myectomy from 2007 to 2016 were reviewed. Those who had an overnight oximetry test within 6 months before myectomy were included in analysis. Oxygen desaturation index was examined continuously and also categorically (SDB [>5/h] and severe SDB [>15/h]). ResultsA total of 619 of 1500 patients undergoing septal myectomy had overnight oximetry tests. Sleep-disordered breathing (oxygen desaturation index >5/h) was identified in 338 (54.6%) patients, and among those patients, 117 (18.9%) were classified as severe. Patients with SDB were older, had greater body mass index and body surface area, were more likely to have arterial hypertension and atrial fibrillation, and had an increased E/e’ ratio on Doppler echocardiography. Notably, there was no difference in preoperative resting left ventricular outflow tract pressure gradient between patients with SDB and those with normal overnight oximetry (55 (interquartile range: 25 to 86) mm Hg versus 52 (interquartile range: 21 to 85) mm Hg; P=.29). There was no difference in age-adjusted survival among patients with normal oximetry compared with those with mild SDB (hazard ratio: 0.98; 95% CI: 0.45 to 2.17), and severe SDB (hazard ratio: 1.06, 95% CI 0.42 - 2.71). ConclusionSleep-disordered breathing is present in more than half of patients with obstructive HCM in whom septal myectomy is indicated, and is mainly associated with aging, overweight, and male sex. However, SDB does not alter survival following septal myectomy.

Discrete Subaortic Stenosis in an Elderly Patient

Discrete subaortic stenosis is an uncommon condition in the elderly population. Echocardiographic examination can be useful for diagnosis with high accuracy. We present a case report of an elderly female patient who presented with accelerated hypertension and was subsequently diagnosed with discrete subaortic stenosis on transthoracic echocardiography. A significant, non-dynamic, left ventricular outflow tract pressure gradient in the presence of aortic regurgitation should raise the possibility of this condition in patients of geriatric age group.

Risk factors for Takotsubo syndrome following cardiac surgery: A case-control study.

Takotsubo syndrome following cardiac surgery is a rare occurrence. However, early diagnosis is essential to prevent treatment which could increase the left ventricular outflow tract pressure gradient in patients with Takotsubo syndrome, and lead to cardiogenic shock. Therefore, our study aimed to identify the incidence of Takotsubo syndrome after cardiopulmonary bypass and the associated risk factors and prognosis. We retrospectively studied 5773 patients who underwent cardiopulmonary bypass between February 2007 and July 2017. Among these, Takotsubo syndrome was diagnosed in 52 (0.9%). To evaluate the risk factors for Takotsubo syndrome, 104 of the remaining 5721 patient were randomly selected as the control group (1:2 ratio). Univariate and multivariate logistic regression analyses were used for risk factor analysis. Majority of patients (69.2%) in the Takotsubo syndrome group underwent mitral valve surgery, compared with 32.7% in the control group. The following risk factors of Takotsubo syndrome were identified: atrio-ventricular valve surgery (odds ratio (OR) 10.5; 95% confidence interval (CI), 2.6-42.5; p = 0.001); and the immediate postoperative use of epinephrine (OR, 3.3; 95% CI, 1.0-10.7; p = 0.05) and dobutamine (OR, 4.8; 95% CI, 1.72-13.3; p = 0.003). Hypertension was a significant protective factor against Takotsubo syndrome following cardiac surgery (OR, 0.22; 95% CI, 0.06-0.73; p = 0.01). Takotsubo syndrome following cardiac surgery is rare. Immediate postoperative use of epinephrine and doputamine, as well as atrio-ventricular valve surgery were factors associated with the development of Takotsubo syndrome.

New stent for transapical mitral valve replacement in acute swine experiment

BackgroundMany patients with mitral regurgitation are denied open-heart surgery due to perceived high risk. Transcatheter mitral valve replacement is a therapeutic alternative for patients at high surgical risk. This study aimed to assess the feasibility of a new self-expanding valved stent for transcatheter mitral valve replacement via apex in an acute animal model.MethodsEight porcine experiments were performed in the acute study. A left thoracotomy was performed, and the new self-expanding transcatheter valved stent was deployed under fluoroscopic guidance in the native mitral annulus via apex. Hemodynamic data were recorded before and after implantation. Mitral annulus diameter and valve area were measured using echocardiography. Transvalvular and left ventricular outflow tract pressure gradients were measured using invasive methods.ResultsSeven animals underwent successful transapical mitral valve replacement; the implantation was unsuccessful in one animal. The mean procedure time, defined from placement to tightening of the purse-string suture, was 17.14 ± 7.86 min. Hemodynamic data before and after transapical mitral valve replacement showed no difference in statistical analysis. The mean diameter of the self-expanding device after implantation was 2.58 ± 1.04 cm; the mean functional area was 2.70 ± 0.26 cm2. Trace-to-mild central and paravalvular leaks were detected in 7 valves. The mean pressure gradient across the self-expanding device was 2.00 ± 0.82 mmHg; the corresponding gradient across the LVOT was 3.28 ± 1.11 mmHg. Postmortem evaluation confirmed precise device positioning in 7 animals with no signs of LVOT obstruction.ConclusionTranscatheter mitral replacement of the new valved stent was confirmed feasible in acute preclinical models. The new stent reveals optimal design parameters.

Influence of operator volume on early outcomes of septal myectomy for isolated hypertrophic obstructive cardiomyopathy.

BackgroundGuidelines on the diagnosis and management of hypertrophic cardiomyopathy (HCM) recommend that septal myectomy be performed by experienced operators. However, the impact of operator volume on surgical treatment outcomes for isolated HCM has been poorly investigated.MethodsFrom 2002 to 2014, 435 consecutive patients with isolated HCM undergoing myectomy at the Fuwai Hospital were retrospectively enrolled. All 29 surgeons were divided into beginner surgeons (operator volume ≤20) and experienced surgeons (operator volume >20) according to the guidelines for the diagnosis and treatment of HCM. Propensity score matching of patients in the two groups was performed.ResultsBaseline differences included advanced New York Heart Association classification and older age in the experienced surgeon group. After matching, in the beginner surgeon group (107 cases), residual obstruction (18.7% vs. 0.9%, P<0.001) was more common, and the postoperative left ventricular outflow tract pressure gradient (20.7±15.1 vs. 14.3±7.4 mmHg, P<0.001) was higher than that of the experienced surgeon group. In the experienced surgeon group (107 cases), the incidence of mitral valve replacement (1.9% vs. 11.2%, P<0.001) and permanent pacemaker implantation (1.9% vs. 3.7%, P<0.001) was significantly lower than that in the beginner surgeon group. However, there was no difference in procedural mortality (1.9% vs. 1.9%) between the two groups.ConclusionsOperator volume is an important factor in achieving better obstruction obliteration after septal myectomy in patients with isolated HCM.

Palliative combined cutting and high-pressure balloon valvuloplasty in six dogs with severe, symptomatic subaortic stenosis

Introduction/ObjectivesSevere subaortic stenosis (SAS) is a congenital heart defect in dogs that often results in clinical signs and reduced survival. The objective of this study was to describe characteristics of dogs with severe, symptomatic SAS who underwent combined cutting and high-pressure balloon valvuloplasty (CB/HPBV). Animals, materials, and methodsRetrospective description of the clinical characteristics, CB/HPBV procedural deviations from reported methodology and outcomes in a series of six client-owned dogs with severe, symptomatic SAS. ResultsBreeds included two each of Newfoundland, Golden retriever, and German shepherd. Median age was 10.1 months (range: 5–72.3 months), and median weight was 25.5 kg (range: 21.8–36.4 kg). Before CB/HPBV, clinical signs were present in all dogs; four were managed for congestive heart failure (CHF). Three dogs had concurrent congenital heart disease. Median Doppler-estimated left ventricular outflow tract pressure gradient was pre-operatively 149.7 mmHg (range: 89.9–254.7 mmHg) and post-operatively 134.1 mmHg (range: 83.9–181.2 mmHg). Median aortoseptal angle was steep at 136° (range: 109–143°). Clinical improvement was documented in all dogs, based on temporary discontinuation of diuretics and/or owner-perceived reduction in clinical signs. At the time of writing, three dogs had died suddenly, one was euthanized because of recurrence of clinical signs, and one died in CHF. Median survival time was 26.4 months after procedure (range: 6.3–45.8 months). One dog remained alive at 44 months after procedure. ConclusionsPalliative CB/HPBV is a potential therapeutic option for dogs with severe, symptomatic SAS complicated by concurrent congenital heart disease, arrhythmias, or CHF.