Left Ventricular Outflow Tract Pressure Research Articles

Minimally Invasive Surgery for Hypertrophic Obstructive Cardiomyopathy With Mitral Regurgitation

To summarize the safety and effect of minimally invasive surgery for hypertrophic obstructive cardiomyopathy (HOCM) with significant mitral regurgitation through a single transaortic approach via right minithoracotomy. From 2008 to 2017, 51 HOCM patients with significant mitral regurgitation underwent minimally invasive surgery via right minithoracotomy. Preoperative peak left ventricular outflow tract pressure gradient (LVOTPG) was 96.53 ± 28.72 mm Hg. Preoperative average interventricular septum thickness was 24.31 ± 3.52 mm. All patients had significant mitral regurgitation with systolic anterior motion phenomenon. An oblique incision was made on the anterior wall of ascending aorta or aortic root. Modified Morrow procedure and edge-to-edge mitral valvuloplasty were performed through the single transaortic approach via right minithoracotomy. All patients successfully underwent the minimally invasive surgery through the single transaortic approach via right minithoracotomy. At discharge, postoperative peak LVOTPG (18.16 ± 6.41 mm Hg) and interventricular septum thickness (14.33 ± 1.99 mm) were significantly decreased compared with preoperative values (P < .05). All patients had no or trivial mitral regurgitation. The average peak mitral valve pressure gradient was 3.39 ± 1.82 mm Hg. Systolic anterior motion phenomenon disappeared in all patients. During follow-up, peak LVOTPG was 19.27 ± 6.10 mm Hg; average interventricular septum thickness was 14.67 ± 1.87 mm. All patients had no or trivial mitral regurgitation. Average peak mitral valve pressure gradient was 3.04 ± 1.52 mm Hg. No systolic anterior motion phenomenon occurred. Minimally invasive surgery of modified Morrow procedure and edge-to-edge mitral valvuloplasty through a single transaortic approach via right minithoracotomy could be safely and effectively applied for patients with HOCM and significant mitral regurgitation, which could also effectively eliminate systolic anterior motion phenomenon and without mitral valve stenosis.

Relationship between Left Ventricular Outflow Tract Pressure Gradient and Hemoglobin in Patients with Hypertrophic Cardiomyopathy.

Anemia caused by left ventricular outflow tract obstruction in patients with hypertrophic obstructive cardiomyopathy (HOCM) has been reported, however, large clinical studies confirming this association are lacking. The objective of the present study was to investigate the relationship between left ventricular outflow tract (LVOT) pressure gradient and hemoglobin in patients with hypertrophic cardiomyopathy (HCM). Patient demographics, laboratory and echocardiography data from 310 patients diagnosed with HCM from our hospital who had undergone echocardiography from July 2014 to March 2019 were collected from medical records. Patients were classified into HOCM and non-HOCM groups. Compared to the non-HOCM group, patients in the HOCM group had a lower hemoglobin level (112.2 ± 16.7 vs. 132.9 ± 22.2 g/L, p < 0.001). In addition, significant negative correlations between hemoglobin and LVOT pressure gradient were found in males (r = -0.568, p < 0.001) and females (r = -0.589, p < 0.001). Receiver operating characteristic curve analysis revealed that the best cut-off value for hemoglobin to predict HOCM in male patients was 128 g/L with 74.19% sensitivity and 75.51% specificity (area under the curve: 0.763, p < 0.001). For female patients, the cut-off value was 125 g/L, with a sensitivity and specificity of 89.39% and 48.48%, respectively (area under the curve: 0.718, p < 0.001). Our results indicate that hemoglobin level is inversely proportional to the LVOT gradient pressure and has value for predicting outflow tract obstruction in patients with HCM.

Correlation between three-dimensional speckle tracking echocardiography combined with cardiac magnetic resonance imaging-late gadolinium enchancemet on left ventricular global systolic function and myocardial fibrosis in adult hypertrophic cardiomyopathy

Objective To evaluate the left ventricular global systolic function and myocardial fibrosis in adult hypertrophic cardiomyopathy (HCM) patients by three-dimensional speckle tracking echocardiography(3D-STE) combined with cardiac magnetic resonance imaging-late gadolinium enchancemet (CMRI-LGE) sequence, and to explore the association between left ventricular global systolic function and myocardial fibrosis. Methods Thirty patients with HCM(HCM group) and 33 healthy controls(control group) were enrolled in the study. All patients underwent conventional two-dimensional echocardiography (2DE), tissue Doppler imaging (TDI), and 3D-STE. The following parameters were acquired and compared between the groups: interventricular septal end-diastolic thickness (IVSD), left ventricular posterior wall end-diastolic thickness (LVPWD), left ventricular mass(LVM), left ventricular mass index (LVMI), left atrial volume (LAV), and left ventricular end-systolic volume(LVESV), left ventricular end-diastolic volume (LVEDV), left ventricular outflow tract pressure gradient (LVOT-PG), left ventricular outflow tract velocity time integral (LVOT-VTI), isovolumic relaxation time (IVRT), global strain (GS), global longitudinal strain (GLS), global radial strain (GRS), global circumferential strain (GCS). And 28 patients who met the CMRI indications underwent CMRI-LGE to obtain the LVM, and the correlation and consistency of LVM results obtained from CMRI and 3D-STE were performed.According to LGE results, HCM patients were divided into LGE(+ ) group and LGE (-) group, the differences of GLS, GRS and GCS between the two groups were analyzed. Results ①Compared with the control group, IVSD, LVPWD, LVMI, LAV, LVOT-PG, LVOT-VTI and IVRT were significantly increased in the HCM group (all P 0.05), while GLS and GRS decreased and GCS increased significantly in HCM group (P<0.05); ③The correlation between 3D-STE and CMRI in measuring measured LVM in HCM patients was good, and the results showed good concordance(r=0.807, P<0.01). ④GLS in LGE(+ ) group was lower than in LGE(-) group(P=0.004), but there was no significant difference in GCS and GRS between the two groups(P=0.597, 0.534). Conclusions ①3D-STE can detect the early damage of left ventricular global systolic function in patients with HCM; ②3D-STE combined with CMRI-LGE technology can provide an important imaging reference for the evaluation of the relationship between left ventricular global systolic function and myocardial fibrosis in patients with HCM. Key words: Echocardiography; Three-dimensional speckle tracking imaging; Cardiomyopathy, hypertrophic; Cardiac magnetic resonance imaging; Ventricular function, left; Myocardial fibrosis

Quantification of left ventricular performance in different phenotypes of hypertrophic cardiomyopathy

Objective To evaluate the characteristics of left ventricular structure, function, myocardial mechanics, hemodynamics and synchrony in different phenotypes of hypertrophic cardiomyopathy (HCM) using state-of-the-art echocardiography. Methods A consecutive series of 85 adult HCM patients who were admitted to the Xi Jing HCM center from January 2016 to November 2017 were collected. According to the peak left ventricular outflow tract pressure gradient in exercise stress echocardiography, the patients were divided into three groups: patients with non-obstructive HCM (n=28), those with labile-obstructive HCM (n=27), and those with obstructive HCM (n=30). In addition, 16 normal family members of HCM patients were included as control group. Two-dimensional speckle tracking imaging, tissue Doppler imaging and exercise stress echocardiography were used to evaluate the left ventricular function in resting and exercise states. Results ①As compared with the control group, left ventricular end-diastolic diameter decreased and left ventricular ejection fraction increased in all three HCM groups(all P 0.05). The obstructive HCM had the lowest mitral annular plane systolic excursion (MAPSE) and s′, and the longest systolic peaking time standard deviation(Ts-SD) and early diastolic peaking time standard deviation(Te-SD) (all P<0.05). The left ventricular diastolic function of obstructive HCM (e′, the E/e′ ratio and the left atrial volume index) was the worst, labile-obstruction and non-obstructive HCM were better, and the control group was the best (all P<0.001). ③During exercise, the GLS, GCS, GRS, twist of the left ventricle and the MAPSE were the lowest in the obstructive HCM, which increased in the labile-obstructive and non-obstructive HCM, and were best in the control group. The Ts-SD and Te-SD were the shortest in the control group, were prolonged in non-obstructive and labile-obstruction HCM, and were longest in obstructive HCM (all P<0.05). Additionally, the exercise time of the control group was the longest, followed by non-obstructive and labile-obstruction HCM, and the shortest in the obstructive HCM (all P<0.05). The METs of obstructive HCM were significantly lower than the other three groups (all P<0.05). Conclusions In obstructive HCM, the left ventricular systolic strain and synchronization, as well as the MAPSE, are significantly impaired in patients both at rest and during exercise. The patients with labile-obstructive and non-obstructive HCM have reduced left ventricular GLS, twist, and e′, but normal left ventricular GCS, GRS, synchrony, and MAPSE at rest, which are all impaired during exercise. Key words: Two-dimensional speckle tracking imaging; Tissue Doppler imaging; Hypertrophic cardiomyopathy; Exercise stress echocardiography; Myocardial mechanics; Synchrony

An echocardiographic study of left ventricular torsion in patients with latent obstructive hypertrophic cardiomyopathy

Objective To explore the changes of left ventricular torsion function in patients with latent obstructive hypertrophic cardiomyopathy(HCM), and provide quantitative informations for clinical evaluation of cardiac function. Methods A total of 49 consecutive patients with HCM without left ventricular outflow tract obstruction at rest were enrolled.All subjects underwent exercise stress echocardiography. After exercise left ventricular outflow tract pressure gradient(LVOT-PG)≥30 mmHg was positive for exercise stress test (latent obstruction), while LVOT-PG<30 mmHg was negative for exercise stress test (non-obstruction). An ultrasound system obtained two-dimensional ultrasound images of resting and moving peaks. The global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS) of the left ventricle 16 segments and left ventricular rotation, twist were analysis using off-line EchoPAC software. The differences of the above parameters were compared between the two groups. Results There were no significant differences in GLS, GRS, GCS and Rotation-B between the two groups in resting and peak period of exercise (all P>0.05), GRS in both groups were significantly increased compared with that before exercise (all P 0.05). Conclusions Left ventricular torsion function is significantly changed in rest and after exercise in latent obstructive HCM patients, providing valuable quantitative information for clinical comprehensive evaluation of cardiac function. Key words: Echocardiography, stress; Latent left ventricular outflow tract obstruction; Cardiomyopathy, hypertrophic; Two-dimensional strain; Left ventricular twist

Thick Hearts Can't Keep Up: Exercise Limitations in Patients With Hypertrophic Cardiomyopathy

Patients with hypertrophic cardiomyopathy (HCM) may experience intolerance to submaximal and maximal exercise. While ejection fraction is generally preserved, reduced left ventricular end diastolic volume may limit stroke volume reserve and potentially attenuate maximal oxygen uptake (V̇O2max). Whether the relationship between supply (cardiac output, Q̇c) and demand (oxygen uptake, V̇O2) remains intact in these patients is unclear.PURPOSETo quantify the cardiac output response to a given metabolic demand during submaximal and maximal exercise in patients with HCM.METHODSEight patients with HCM (45.8±8.8 years, 75% female, left ventricular outflow tract pressure gradient 13±12mmHg) completed two bouts of submaximal steady‐state treadmill exercise (SS1 ~45% and SS2 ~60% V̇O2max), followed by an incremental treadmill test to exhaustion. V̇O2 (Douglas bag technique), Q̇c, (acetylene rebreathing), stroke volume (Q̇c/heart rate) and arterio‐venous difference (av‐O2 diff, Fick principle) were measured during rest, SS1, SS2 and maximal exercise. Stroke volume reserve was calculated as the percent increase in stroke volume from rest to maximal exercise. The relationship between Q̇c and V̇O2 (Q̇c/V̇O2 slope) was quantified using data collected at rest, submaximal and maximal exercise. Healthy sedentary adults (n=8) and subjects with left ventricular hypertrophy from hypertension (LVH, n=8) were included for age and sex‐matched comparison.RESULTSPatients with HCM had lower relative V̇O2max than healthy subjects and patients with LVH (HCM: 21.1±4.8mL/kg/min, healthy: 27.5±3.4 mL/kg/min, LVH 24.4±7.5 mL/kg/ min). The Q̇c response to a given metabolic demand was impaired in patients with HCM when compared to healthy controls and patients with LVH (HCM: 4.6, control: 5.4, LVH: 5.5; Figure 1). The blunted Q̇c/V̇O2 slope was primarily due to a smaller stroke volume reserve (HCM 28.8±27.0%, healthy 52.2±19.6%, LVH 48.6±25.0%), but also a significantly lower maximal heart rate compared to healthy controls (154±24 vs. 178±10 beats per minute, respectively; P&lt;0.05), though 75% of HCM patients were on beta‐blockade and/or calcium channel‐blockade therapy. Remarkably, five HCM patients were able to compensate for a blunted Q̇c/V̇O2 slope (4.2±0.4) and still achieve &gt;80% of predicted V̇O2max by significantly augmenting av‐O2 diff from rest to maximal exercise (Δav‐O2 diff 10.6±1.6 vs. 6.2±1.5 in HCM patients who did not achieve 80% of predicted V̇O2 max, P&lt;0.05).CONCLUSIONAlthough ejection fraction is preserved, patients with HCM may be unable to sufficiently match Q̇c to metabolic demands. However, some patients appear to compensate by significantly augmenting peripheral oxygen extraction and achieve at least 80% of predicted V̇O2max.Support or Funding InformationSupported by The Center for Regenerative Science and Medicine, UTSW Medical Center, Biotronik Inc., and the Research Endowment from The American College of Sports Medicine Foundation.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Comparison of Clinical Effects between Percutaneous Transluminal Septal Myocardial Ablation and Modified Morrow Septal Myectomy on Patients with Hypertrophic Cardiomyopathy

Background:Percutaneous transluminal septal myocardial ablation (PTSMA) and modified Morrow septal myectomy (MMSM) are two invasive strategies used to relieve obstruction in patients with hypertrophic cardiomyopathy (HCM). This study aimed to determine the clinical outcome of these two strategies.Methods:From January 2011 to January 2015, 226 patients with HCM were treated, 68 by PTSMA and 158 by MMSM. Both ultrasonic cardiograms and heart functional class were recorded before, after operations and in the follow-up. Categorical variables were compared using Chi-square or Fisher's exact tests. Quantitative variables were compared using the paired samples t-test.Results:Interventricular septal thickness was significantly reduced in both groups (21.27 ± 4.43 mm vs. 18.72 ± 4.13 mm for PTSMA, t = 3.469, P < 0.001, and 21.83 ± 5.03 mm vs. 16.57 ± 3.95 mm for MMSM, t = 10.349, P < 0.001, respectively). The left ventricular outflow tract (LVOT) pressure gradient (PG) significantly decreased after the operations in two groups (70.30 ± 44.79 mmHg vs. 39.78 ± 22.07 mmHg for PTSMA, t = 5.041, P < 0.001, and 74.58 ± 45.52 mmHg vs. 13.95 ± 9.94 mmHg for MMSM, t = 16.357, P < 0.001, respectively). Seven patients (10.29%) in the PTSMA group required a repeat operation in the follow-up. Eight (11.76%) patients were evaluated for New York Heart Association (NYHA) III/IV in the PTSMA group, which was significantly more than the five (3.16%) in the same NYHA classes for the MMSM group at follow-up. Less than 15% of patients in the PTSMA group and none of the patients in the MMSM group complained of chest pain during follow-up.Conclusions:Both strategies can not only relieve LVOT PG but also improve heart function in patients with HCM. However, MMSM might provide a more reliable reduction in gradients compared to PTSMA.

Limited value of end-expiratory inferior vena cava diameter to predict fluid responsiveness impact of intra-abdominal pressure.

We sought to determine the diagnostic ability of the end-expiratory inferior vena cava diameter (IVCEE) to predict fluid responsiveness (FR) and the potential confounding effect of intra-abdominal pressure (IAP). In this multicenter study, 540 consecutive ventilated patients with shock of various origins underwent an echocardiographic assessment by experts. The IVCEE, velocity time integral (VTI) of the left ventricular outflow tract (LVOT) and intra-abdominal pressure (IAP) were measured. Passive leg raising (PLR) was then systematically used to perform a reversible central blood volume expansion. FR was defined by an increase in LVOT VTI ≥10% after 1min of PLR. Since IVCEE was not obtained in 117 patients (22%), 423 were studied (septic shock: 56%), 129 of them (30%) having elevated IAP (≥12mmHg) and 172 of them (41%) exhibiting FR. IVCEE≤13mm predicted FR with a specificity of at least 80% in 62 patients (15%), while IVCEE≥25mm predicted the absence of FR with a specificity of at least 80% in 61 patients (14%). In the remaining 300 patients (71%), the intermediate value of IVCEE did not allow predicting FR. An adjusted relationship between IVCEE and FR was observed while this relationship was less pronounced in patients with IAP≥12mmHg. Measurement of IVCEE in ventilated patients is moderately feasible and poorly predicts FR, with IAP acting as a confounding factor. IVCEE might add some value to guide fluid therapy but should not be used alone for fluid prediction purposes.

Computational Modelling of Transcatheter Mitral Valve Replacement to Predict Post–Procedural Haemodynamics

Background: Recent advances in computed tomography (CT)-based modelling can be used for pre–procedural planning of transcatheter mitral valve replacement (TMVR). We aimed to develop a CT-based computational model of prosthesis placement to investigate post–procedural blood flow, mean flow kinetic energy, and left ventricular outflow tract (LVOT) pressure gradients.

The Effects of Surgical Myectomy on Left Ventricular Mechanics in Patients with Hypertrophic Obstructive Cardiomyopathy

Background: Hypertrophic obstructive cardiomyopathy (HOCM) is an inherited disorder, characterized by left ventricle outflow tract obstruction. We performed this study to investigate the changes in left ventricular mechanics after surgical myectomy in patients with HOCM. Materials and methods: We enrolled 15 patients with HOCM referred to surgical myectomy according to the recommendation of American Heart Association. All patients underwent transthoracic 2D speckle-tracking echocardiography to measure cardiac dimensions and mechanics before and after surgery. statistical analyses were performed using GraphPad Instat and MedCalc software. Results: Following myectomy, all patients reported improved symptoms and increased functional capacity. Conventional echocardiographic measurements showed that surgical myectomy significantly decreased left atrial volume index (r=0.83, p˂0.0001), interventricular septum thickness (p˂0.0001, r=0.79), left-ventricular mass index (p˂0.0001, r=0.49) and resting left-ventricular outflow tract pressure gradient (p˂0.0001, r=-0.03). In terms of leftventricular function, we observed significant decreases in fractional shortening (r=0.16, p˂0.0001) and ejection fraction (p=0.01, r=-0.04) after the procedure in comparison to baseline functional data. We further significant postoperative reductions in terms of average circumferential strain (p˂0.0001, r=0.49), basal rotation (p=0.03, r=0.97), apical rotation (p˂0.0001, r=0.94) and LV twist (p˂0.0001, r=0.96). However, no significant changes were observed after myectomy in terms of most longitudinal strain and left ventricular synchrony measures. Conclusion: Surgical myectomy improves symptoms, relieves left ventricular outflow tract obstruction and decreases left atrial volume index in patients with HOCM, but shows no significant changes in LV longitudinal strain and LV synchrony measures. Future studies should employ a larger sample size and more sensitive methods of synchrony detection.

Predicting value of 2014 European guidelines risk prediction model for sudden cardiac death (HCM Risk-SCD) in Chinese patients with hypertrophic cardiomyopathy

Objective: To evaluate the predicting value of the 2014 European Society of Cardiology (ESC) guidelines risk prediction model for sudden cardiac death (HCM Risk-SCD) in Chinese patients with hypertrophic cardiomyopathy (HCM), and to explore the predictors of adverse cardiovascular events in Chinese HCM patients. Methods: The study population consisted of a consecutive 207 HCM patients admitted in our center from October 2014 to October 2016. All patients were followed up to March 2017. The 5-year SCD probability of each patient was estimated using HCM Risk-SCD model based on electrocardiogram, echocardiography and cardiac magnetic resonance (CMR) examination results. The primary, second, and composite endpoints were recorded. The primary endpoint included SCD and appropriate ICD therapy, identical to the HCM Risk-SCD endpoint. The second endpoint included acute myocardial infarction, hospitalization for heart failure, thrombus embolism and end-stage HCM. The composite endpoint was either the primary or the second endpoint. Patients were divided into the 3 categories according to 5-year SCD probability assessed by HCM Risk-SCD model: low risk group<4%,intermediate risk group ≥4% to<6%, and high risk group≥6%. Results: (1) Prevalence of endpoints: All 207 HCM patients completed the follow-up (350 (230, 547) days). During follow-up, 8 (3.86%) patients reached the primary endpoints (3 cases of SCD, 3 cases of survival after defibrillation, and 2 cases of appropriate ICD discharge); 21 (10.14%) patients reached the second endpoints (1 case of acute myocardial infarction, 16 cases of heart failure hospitalization, 2 cases of thromboembolism, and 2 cases of end-stage HCM). (2) Predicting value of HCM Risk-SCD model: Patients with primary endpoints had higher prevalence of syncope and intermediate-high risk of 5-year SCD, as compared to those without primary endpoints (both P<0.05). (3) Predicting value of HCM Risk-SCD model: The low risk group included 122 patients (59%), the intermediate risk group 42 (20%), and the high risk group 43 (21%). There was a clear trend towards to higher heart rate, higher values of PTF(V1) and plane QRS-T angle, higher left ventricular mass index (LVMI), elevated maximal left ventricular outflow tract pressure gradient (LVOT-PGmax), enlarged left atrial dimension(LAD) and volume index (LAVI), reduced systolic mitral annular velocity (s'), and higher late gadolinium enhancement (LGE) volume and mass in patients with high risk of 5-year of SCD, as compared to those with low-intermediate risk (all P<0.05). Moreover, 5-year SCD probability was positively correlated with heart rate, plane QRS-T angle, LVMI, LAVI, LGE%, and negatively correlated with s'(r=0.161, P=0.019; r=0.669, P=0.001; r=0.206, P=0.004; r=0.284, P=0.000; r=0.351, P=0.000; r= -0.245, P=0.001; respectively). (4) LAD, LAVI, e' and s' were independent predictors for poor outcomes. HCM patients with LAD≥39 mm, LAVI≥49.6 ml/m(2), e'≤6.5 cm/s and s'≤6.6 cm/s were more likely to have adverse cardiovascular events (AUC 0.702, 95%CI 0.604-0.799, P=0.001; AUC 0.700, 95%CI 0.567-0.833, P=0.001; AUC 0.716, 95%CI 0.616-0.817, P=0.000; AUC 0.764, 95%CI 0.676-0.853, P=0.000,respectively). Conclusions: The HCM Risk-SCD model is of value in predicting SCD for Chinese HCM patients. The plane QRS-T angle and LGE% are the best predictors of 5-year SCD risk in Chinese HCM patients. Moreover, conventional echocardiographic parameters, including LAD, LAVI, e' and s', are useful to predict adverse cardiovascular events among Chinese HCM patients.

Impact of peak provoked left ventricular outflow tract gradients on clinical outcomes in hypertrophic cardiomyopathy

BackgroundHypertrophic cardiomyopathy (HCM) is traditionally classified based on a left ventricular outflow tract (LVOT) pressure gradient of 30mmHg at rest or with provocation. There are no data on whether 30mmHg is the most informative cut-off value and whether provoked gradients offer any information regarding outcomes. MethodsResting and provoked peak LVOT pressure gradients were measured by Doppler echocardiography in patients fulfilling guidelines criteria for HCM. A composite clinical outcome including new onset atrial fibrillation, ventricular tachycardia/fibrillation, heart failure, transplantation, and death was examined over a median follow-up period of 2.1years. ResultsAmong 536 patients, 131 patients had resting LVOT gradients greater than 30mmHg. Subjects with higher resting gradients were older with more cardiovascular events. For provoked gradients, a bi-modal risk distribution was found. Patients with provoked gradients >90mmHg (HR 3.92, 95% CI 1.97–7.79) or <30mmHg (HR 2.15, 95% CI 1.08–4.29) have more events compared to those with gradients between 30 and 89mmHg in multivariable analysis. The introduction of two cut-off points for provoked gradients allowed HCM to be reclassified into four groups: patients with “benign” latent HCM (provoked gradient 30–89mmHg) had the best prognosis, whereas those with persistent obstructive HCM had the worst outcome. ConclusionsProvoked LVOT pressure gradients offer additional information regarding clinical outcomes in HCM. Applying cut-off points at 30 and 90mmHg to provoked LVOT pressure gradients further classifies HCM patients into low-, intermediate- and high-risk groups.

Clinical features of the systolic anterior motion of the mitral valve among patients without hypertrophic cardiomyopathy

BackgroundThe prevalence and clinical features of the systolic anterior motion of the mitral valve (SAM) without hypertrophic cardiomyopathy (HCM) have not been studied well. MethodsRecords of 9180 sequential patients who underwent echocardiography at Tokyo Women's Medical University Hospital were reviewed. SAM patients were divided into those with HCM (HCM; n=60, 68%) and those without HCM (non-HCM; n=28, 32%). To assess SAM morphology, non-HCM patients were divided into the valvular and chordal groups. ResultsThe prevalence of non-HCM SAM was 0.3%. Non-HCM patients showed older age (65.7±15.0 years vs. 56.9±16.8 years, p=0.02), higher prevalence of sigmoid septum (75% vs. 50%, p=0.03), and lower left ventricular outflow tract pressure gradient (LVOT-PG) (27±31mmHg vs. 43±41mmHg, p=0.03) than HCM patients. However, 8 of 28 non-HCM patients showed a LVOT-PG >30mmHg. Valvular SAM showed higher dyspnea prevalence (29% vs. 0%, p=0.04), higher LVOT-PG (39±36mmHg vs. 6±2mmHg, p<0.001), longer anterior mitral leaflet (28±2mm vs. 26±3mm, p=0.04) and more pronounced mitral regurgitation than chordal SAM. ConclusionNon-HCM SAM prevalence was 0.3% in the Japanese population. Non-HCM SAM correlated with older age, sigmoid septum, and a lower LVOT-PG compared with HCM SAM. Among non-HCM SAM, valvular SAM showed a significant symptom, higher LVOT-PG, and more pronounced mitral regurgitation than chordal SAM.

Relationship of basal-septal fibrosis with LV outflow tract obstruction in hypertrophic cardiomyopathy: insights from cardiac magnetic resonance analysis.

Myocardial fibrosis is frequently observed and may be associated with the prognosis in patients with hypertrophic cardiomyopathy (HCM); however, the clinical pathophysiological features, particularly in terms of fibrosis, of hypertrophic obstructive cardiomyopathy (HOCM) remain unclear. This study aimed to determine a role of local fibrosis in HOCM using cardiac magnetic resonance (CMR). 108 consecutive HCM patients underwent CMR. HOCM was defined as a left ventricular outflow tract (LVOT) pressure gradient ≥30mmHg at rest. Myocardial mass and fibrosis mass by late gadolinium-enhancement CMR (LGE-CMR) were calculated and the distribution/pattern was analyzed using the AHA 17-segment model. LV ejection fraction (LVEF) was significantly higher in patients with HOCM (n=19) than in those with nonobstructive HCM (n=89) (P<0.05). Both total myocardial and fibrosis masses in LV were similar in the two groups (P=0.385 and P=0.859, respectively). However, fibrosis in the basal septum was significantly less frequent in the HOCM group than in the nonobstructive HCM group (P<0.01). The LVOT pressure gradient was significantly higher in the basal-septal non-fibrosis group than in the fibrosis group (23.6±37.3 vs. 4.8±11.4mmHg, P<0.01). Multivariate analysis revealed that basal-septal fibrosis was an independent negative predictor of LVOT obstruction in addition to the local wall thickness and LVEF as positive predictors in HCM patients. In conclusion, a significant association was observed between LVOT obstruction and basal septal fibrosis by LGE-CMR in HCM patients. In addition to negative impact of basal-septal fibrosis, basal-septal hypertrophy and preserved global LV contractility may be associated with the pathophysiological features of LVOT obstruction.

New Self-Expanding Transcatheter Valve for Off-Pump Transatrial Mitral Valve-In-Ring Implantation

Objectives: To validate a self-expanding transcatheter valve for off-pump transatrial mitral valve-in-ring (VIR) implantation via a left thoracotomy. Methods: Mitral valve annuloplasty was performed via sternotomy during cardiopulmonary bypass on 9 pigs. After successful weaning from extracorporal circulation, the custom-made, self-expanding transcatheter VIR device was deployed under fluoroscopic guidance within the annuloplasty ring via a left thoracotomy. Hemodynamic data before and after the implantation were recorded. Mitral annulus diameter and valve area were measured by echocardiography. Transvalvular and left-ventricular outflow-tract pressure gradient were measured invasively. Results: Eight successful implantations were performed. Implantation failed in 1 pig because of difficulty with technical delivery of the sheath. Mean transatrial procedure time was 12.6 ± 1.7 min. Hemodynamic status during transatrial implantation was stable, and differences were not statistically significant. Mean mitral annulus diameter and mean mitral orifice area were 2.32 ± 0.2 and 3.84 ± 0.55 cm², respectively. Mild regurgitation was detected in 7 animals and moderate regurgitation in 1. Mean gradients were 6.1 ± 5.0 mm Hg across the device. Postmortem examination confirmed adequate positioning of devices within the annuloplasty ring. Conclusions: This custom-made transcatheter device allows for safe and reproducible off-pump transatrial mitral VIR implantations. Transatrial access is a promising route to facilitate VIR implantations. Our custom-made stent-valve may be suitable for VIR procedures.

Phosphodiesterase 5 Inhibitor Use in Men With Hypertrophic Cardiomyopathy

The prevalence of sexual dysfunction (SD) in men with hypertrophic cardiomyopathy (HC) remains unknown, yet its clinical relevance may be high given that its treatment-phosphodiesterase 5 inhibitors (PDE5i)-can increase the left ventricular outflow tract pressure gradient. In this retrospective study, we evaluated the medical records of consecutively seen men with HC for the evidence of SD (defined as SD diagnosis noted in the medical record, the use of medications unique for SD, or SD reported by the patient on a routine clinical questionnaire). Of the 283 consecutively seen men with HC (mean age 52.9 ± 14.1years), 63patients (22%) with SD were identified. Of those with SD, 38% were recorded as regularly using PDE5i. In conclusion, SD and the use of PDE5i present a relatively common occurrence in men with HC, and further studies are needed to develop an evidence-guided algorithm for safe implementation of SD therapies in this most common inherited cardiomyopathy.

Assessment of left ventricular systolic dyssynchrony in hypertrophic cardiomyopathy by three-dimensional speckle tracking echocardiography

Objective To explore the value of three-dimensional speckle tracking imaging (3D-STI) in evaluating the systolic dyssynchrony of left ventricle(LV) in patients with hypertrophic cardiomyopathy (HCM).Methods A total of 93 consecutive patients with HCM were enrolled,in which 63 patients were non-obstructive HCM (HNCM),30 patients were obstructive HCM(HOCM).In addition,72 healthy subjects were recruited as a control group.An ultrasound system iE33(Philips Medical Systems) was used to acquire and analyze two-dimensional images.Full-volume three-dimensional dynamic images were performed using matrix transducer X5-1.The 16 segments of the time to peak area strain(TAS),the time to peak circumferential strain(TCS),the time to peak longitudinal strain(TLS),the time to peak radial strain(TRS)were analysis using off-line TomTec software (4D LV-Analysis 3.0).Then the standard deviation for the TAS,TCS,TLS,TRS (TAS-SD,TCS-SD,TLS-SD,TRS-SD),the maximal difference value of any of two segments of TAS,TCS,TLS,TRS (TAS-diff,TCS-diff,TLS-diff,TRS-diff),and the indices after standardization(TAS-SD％,TCS-SD％,TLS-SD％,TRS-SD％,TAS-diff％,TCS-diff％,TLS-diff％,TRS-diff％) were calculated,the difference of all these dyssynchroy indices among three groups were compared.Results Compared with the control group,LV end-diastolic,volumes and stroke volume significantly decreased,LV mass and LV diastolic wall thickness significantly increased(P ＜0.05).However,there was no significant difference between LVEF (P ＞0.05).The comparison of the 3D-STI dyssynchrony indices were as followed:compared with the control group,TAS-SD％,TLS-SD％,TRS-SD％,TAS-diff％,TRS-diff％,TLS-diff％ were significantly prolonged in HCM,there were significantly difference(P ＜0.05),while there were no statistics difference in TCS-SD％,TCS-diff％.Compared with the HNCM,TAS-SD％,TCS-SD％,TRS-SD％,TAS-diff％,TRS-diff％,TCS-diff％ were significantly prolonged in HOCM,while there was no statistics difference in TLS-SD％,TLS-diff％.A positive linear correlation exists between left ventricular outflow tract pressure gradient(LVOT-PG) and these dyssynchrony indices.Conclusions The systolic dyssynchrony of the LV are commonly existed in patients with HCM,indicated the impairment of myocardial contractility exists at the early stage of the HCM,3D-STI provided a new method for evaluating LV systolic abnormal in patients with HCM. Key words: Echocardiography; Cardiomyopathy, hypertrophic; Ventricular function, left; Three-dimensional speckle tracking imaging

STRESS IMAGING IN A MAN WITH HYPERTROPHIC CARDIOMYOPATHY AND ERECTILE DYSFUNCTION

The management of erectile dysfunction (ED) in men with hypertrophic cardiomyopathy (HCM) remains controversial, since phosphodiesterase 5 (PDE5) inhibitors can theoretically increase left ventricular outflow tract (LVOT) pressure gradient (PG), yet this increase may not be detected at rest. An

Ascending aorta flow derangement is a marker of outflow obstruction in hypertrophic cardiomyopathy

Background Alterations in systolic blood flow are a characteristic finding in patients with obstructive hypertrophic cardiomyopathy (HCM). Echocardiography is the gold standard for hemodynamic assessment in HCM, but this technique is generally limited to measurement of the left ventricular outflow tract (LVOT) pressure gradient and may not provide a complete description of the hemodynamic impact of the disease. In this study, we sought to employ time-resolved, three-dimensional phase contrast (4D flow) MRI to visualize and quantify 3D blood flow patterns in the LVOT and ascending aorta (AAo) in patients with obstructive and nonobstructive HCM. Methods Obstructive (n = 12) and non-obstructive (n = 18) HCM patients as well as 10 normal volunteers were included in this IRB-approved study. Obstruction was defined as LVOT pressure gradient > 30 mmHg on patients’ most recent echocardiography study (ΔPecho). Septal thickness, LVOT diameter and septum/free wall ratio were measured on SSFP cine MRI. 4D flow MRI data analysis included correction for eddy currents and velocity aliasing, followed by flow visualization and quantification in dedicated software (EnSight, CEI, Apex, NC). 3D blood flow patterns within the LVOT and AAo were graded for the presence of helical flow (absent = 0, mild/moderate = 1, severe = 2) by two observers blinded to diagnosis, and the results were averaged. MRI-measured pressure gradient (ΔPMRI) was calculated from the peak systolic 3D blood velocity profile within the LVOT using the simplified Bernoulli equation. (Figure 1) The Mann-Whitney U test was used to compare groups and Spearman’ s( rS) or Pearson’s (r) correlations were used as appropriate. Results

Stress Imaging in Men with Hypertrophic Cardiomyopathy and Erectile Dysfunction

Background: The management of erectile dysfunction in men with hypertrophic cardiomyopathy remains controversial, since phosphodiesterase 5 inhibitors can theoretically increase left ventricular outflow tract pressure gradient (PG), yet this increase may not be detected at rest. Case Description: Two hemodynamic supine bike stress tests with transthoracic echocardiography were performed on two subsequent mornings in a 65-year-old man with hypertrophic cardiomyopathy and episodes of presyncope. The patient was instructed to take Tadalafil before the first stress test, and Tadalafil and Vardenafil before the second stress test. Results: The left ventricular outflow tract PG recorded by continuous-wave Doppler in the transapical view increased between rest and peak exercise: ΔPG on Tadalafil=+37 mmHg; ΔPG on Tadalafil and Vardenafil=+124 mmHg. Conclusion: This report demonstrates a novel use of serial provocation imaging studies aimed at comparing left ventricular PGs at peak stress during the initiation and dose titration of phosphodiesterase 5 inhibitors. Further studies are needed to develop an evidence-guided algorithm for safe implementation of therapies for erectile dysfunction in this most common inherited cardiomyopathy.