Effects of sex on clinical outcomes of hypertrophic cardiomyopathy in Singapore.

Introduction: Despite the growing recognition that sex can affect the presentation and outcomes in hypertrophic cardiomyopathy (HCM), this relationship is understudied in Asians. Therefore, we aimed to explore sex differences in Asian patients with HCM. Method: A total of 295 consecutive patients diagnosed with HCM were recruited from a tertiary cardiology centre from 2010 to 2017 over a mean of 3.9±2.7 years. We evaluated the effects of sex on the outcomes of HCM in Asian patients. Results: HCM patients were more commonly men (72%). Women were older and had more comorbidities, including hypertension and atrial fibrillation. On transthoracic echocardiography, the indexed left ventricular end-systolic and end-diastolic volumes were similar, but more women had more-than-moderate mitral regurgitation and had a smaller left ventricular outflow tract (LVOT). Women more commonly had findings of obstructive physiology with significant LVOT obstruction, defined as >30 mmHg at rest. The use of implantable cardioverter defibrillators was similar across sexes. On multivariable analysis, women were found to be more likely to develop progressive heart failure requiring admission (hazard ratio [HR] 2.10, 95% confidence interval [CI] 1.05-4.71, P=0.021) but had a lower rate of all-cause mortality (HR 0.36, 95% CI 0.19-0.70, P=0.003). Conclusion: Women diagnosed with HCM were older, had more comorbidities and were more likely to develop heart failure while men had a higher risk of all-cause mortality.

Incidence and management of the left ventricular outflow obstruction in patients with atrioventricular septal defects.

OBJECTIVES: Left ventricular outflow tract obstruction (LVOTO) is a recognized complication after complete repair of atrioventricular septal defect (AVSD). This study reviewed the incidence and management of LVOTO following AVSD repair at a single institution. METHODS: From 1975 to 2019, 24 patients (3.3%, 24/730) underwent reoperation due to LVOTO following partial AVSD (pAVSD) and complete AVSD (cAVSD) repair. The data were retrospectively reviewed. RESULTS: The incidence of LVOTO following pAVSD and cAVSD repair was 4.4% (12/275) and 2.6% (12/455). Freedom from LVOTO reoperation following pAVSD and cAVSD repair at 25 years was 94.3% [95% confidence interval (CI); 89.7-96.7] and 95% (95% CI; 91.1-97.3). The median time from complete repair of pAVSD and cAVSD to LVOTO reoperation was 4.4 years [interquartile range (IQR): 3.4-6.7] and 2.6 years (IQR: 2.2-4.7). Freedom from second LVOTO reoperation at 5, 10 and 15 years was 83.7% (95% CI; 57.2-98.2), 59.2% (95% CI; 28.7, 80.3) and 39.5% (95% CI; 13.2-65.3). The median time between the first and the second LVOTO reoperation in the groups of pAVSD and cAVSD was 6.1 years (IQR: 3.4-8.9) and 8.6 years (IQR: 5.7-9.8). There was no significant difference regarding the first (P = 0.7406) and subsequent LVOTO (P = 0.7153) following complete repair of pAVSD and cAVSD. Combined access to the left ventricular outflow tract was not protective regarding LVOTO reoccurrence. Survival for both groups after LVOTO reoperation at 15 years was 95.6% (95% CI 99.4-72.9). CONCLUSIONS: Incidence of LVOTO after AVSD repair is low but the reoccurrence rate is high. Standard subaortic resection does not always provide definitive LVOTO relief. The survival after LVOTO reoperation is excellent.

Concurring hypertrophic cardiomyopathy and takotsubo cardiomyopathy: Assessment and management.

The prevalence of takotsubo cardiomyopathy (TCM) has been on the rise, but co-occurrence with hypertrophic cardiomyopathy (HOCM) remains rare. Although presenting patient demographics were similar to those in TCM, the potential for hemodynamic compromise was significantly compounded by the presence of underlying HOCM. Management was similar to standalone TCM, although use of inotropic agents and mechanical support appears to be more prevalent. Despite the increased potential for complications and the paucity of data regarding management, outcomes appear to be mostly favorable in both the hospitalization period and at follow-up. Interestingly, despite a new diagnosis of HOCM in about half the cases described, which signifies no significant left ventricular outflow tract (LVOT) gradient prior to TCM, half of those patients had a persistently elevated LVOT gradient after resolution of TCM. This poses a question of whether or not TCM can predispose to LVOT obstruction in HOCM patients even after its resolution.

Inducible Left Ventricular Outflow Tract Obstruction in Patients Undergoing Liver Transplantation: Prevalence, Predictors, and Association With Cardiovascular Events.

BACKGROUND: Inducible left ventricular outflow tract obstruction (LVOTO) is often encountered in liver transplantation (LT) candidates during cardiac workup. While the impact of LVOTO on adverse cardiovascular hemodynamics is well reported, it is unclear whether it predisposes to perioperative cardiovascular complications. METHODS: Consecutive patients with end-stage liver disease undergoing dobutamine stress echocardiography (DSE) were evaluated at an LT center between 2010 and 2017. Perioperative major adverse cardiovascular events (MACEs) at 30 days and all-cause death were recorded from a prospectively maintained LT database. RESULTS: We evaluated 560 patients who underwent DSE during LT workup, with LVOTO identified in 24.3% (n = 136). Of these, 309 patients progressed to transplant. Patients with LVOTO demonstrated a lower peak systolic blood pressure (SBP) and an overall reduction in SBP on DSE. A total of 85 MACEs were recorded in 72 patients (23.3%) including 3 deaths, 19 cases of heart failure, 11 cardiac arrests, 8 acute coronary syndromes, and 44 arrhythmias. MACE occurred in 15/64 patients (23.4%) with LVOTO and 57/245 (23.3%) without (P = 0.92). There was an increased risk of perioperative cardiac arrest in patients with LVOTO (7.4% versus 2.4%, P = 0.04). Intraoperatively, patients with LVOTO required higher doses of vasopressors (P = 0.01) and received greater volumes of fluid (10.5 ± 8.1 versus 8.4 ± 6.4 L, P = 0.03). CONCLUSIONS: Patients with end-stage liver disease and LVOTO demonstrate a reduction in SBP during physiological stress that may translate to hemodynamic instability during LT. LVOTO was not associated with an increased rate of perioperative MACE or death.

Outcomes of Patients with Severe Aortic Stenosis and Left Ventricular Obstruction Undergoing Transcatheter Aortic Valve Implantation.

Scarce data exist on clinical features and prognosis of patients with severe aortic stenosis (AS), concomitant with left ventricular obstruction (LVO). We aimed to evaluate the prevalence, characteristics, and outcomes in patients with severe AS and LVO undergoing transcatheter aortic valve implantation (TAVI). Consecutive patients with severe AS undergoing TAVI between January 2013 to December 2017 at our institution were included. Significant LVO was defined as resting peak left ventricular (LV) systolic gradient ≥30 mm Hg on pre-TAVI echocardiography. We analyzed the primary composite outcome of all-cause mortality and rehospitalization for heart failure (HHF) at 1-year in patients with LVO and those without LVO in the overall and propensity-matched populations. Among 1,729 patients who underwent TAVI, significant LVO was observed in 31 (1.8%) patients. This group was more likely to be female, had smaller aortic annulus and LV cavity, and received a smaller size of the transcatheter heart valve. The most common phenotype of LV hypertrophy causing LVO was concentric LV hypertrophy (58%), and mid-LV obstruction was more common than LV outflow tract obstruction (77% vs 23%, respectively). After adjustment for baseline differences, the primary outcome was not significantly different between patients with LVO and those without LVO (15% vs 16%, respectively; hazard ratio: 0.83; 95% confidence interval: 0.19 to 3.72; p = 0.809). In conclusion, in patients undergoing TAVI, concomitant LVO was relatively uncommon and occurred more often at mid-LV. The presence of pre-TAVI LVO was not associated with worse outcomes defined as increase all-cause mortality or HHF at 1-year.

Vasopressin in Patients with Septic Shock and Dynamic Left Ventricular Outflow Tract Obstruction.

PURPOSE: Left ventricular outflow tract obstruction (LVOTO) is a relatively uncommon but severe condition that may lead to hemodynamic impairment. It can be elicited by morphological (left ventricular hypertrophy, sigmoid septum, prominent papillary muscle, prolonged anterior mitral valve leaflet) and functional (hypovolemia, low afterload, hypercontractility, catecholamines) factors. We sought to determine the incidence of the most severe form of LVOTO in septic shock patients and describe the therapeutic effects of vasopressin. METHODS: Over a period of 29 months, 527 patients in septic shock were screened for LVOTO. All were mechanically ventilated and treated according to sepsis bundles, including pre-load optimization and norepinephrine infusion. Vasopressin was added in addition to norepinephrine to reduce the adrenergic burden and decrease LVOTO. RESULTS: Ten patients were diagnosed with the most severe form of LVOTO, including systolic anterior mitral valve motion (SAM) and severe mitral regurgitation (MR) with pulmonary oedema. The median norepinephrine dosage to obtain a mean arterial pressure of ≥70 mmHg was 0.58 mcg/Kg/min (IQR 0.40-0.78). All patients had a hyper-contractile left ventricle, septal hypertrophy, significant LVOTO (peak gradient 78 [56-123] mmHg) associated with SAM and severe MR with pulmonary oedema. Vasopressin (median 4 IU/h) allowed a significant reduction of norepinephrine (0.18 [0.14-0.30] mcg/kg/min; p = 0.01), LVOT gradient (35 [24-60] mmHg; p = 0.01) and MR with a significant paO2/FiO2 increase (174 [125-213] mmHg; p = 0.01). CONCLUSION: Vasopressin allowed a reduction of norepinephrine with subsequent LVOTO reduction and hemodynamic improvement of the most severe form of LVOTO, which represented 1.9% of all septic shock patients.

Association of Obesity With Adverse Long-term Outcomes in Hypertrophic Cardiomyopathy.

Importance: Patients with hypertrophic cardiomyopathy (HCM) are prone to body weight increase and obesity. Whether this predisposes these individuals to long-term adverse outcomes is still unresolved. Objective: To describe the association of body mass index (BMI, calculated as weight in kilograms divided by height in meters squared) with long-term outcomes in patients with HCM in terms of overall disease progression, heart failure symptoms, and arrhythmias. Design, Setting, and Participants: In this cohort study, retrospective data were analyzed from the ongoing prospective Sarcomeric Human Cardiomyopathy Registry, an international database created by 8 high-volume HCM centers that includes more than 6000 patients who have been observed longitudinally for decades. Records from database inception up to the first quarter of 2018 were analyzed. Patients were divided into 3 groups according to BMI class (normal weight group, <25; preobesity group, 25-30; and obesity group, >30). Patients with 1 or more follow-up visits were included in the analysis. Data were analyzed from April to October 2018. Exposures: Association of baseline BMI with outcome was assessed. Main Outcome and Measures: Outcome was measured against overall and cardiovascular mortality, a heart failure outcome (ejection fraction less than 35%, New York Heart Association class III/IV symptoms, cardiac transplant, or assist device implantation), a ventricular arrhythmic outcome (sudden cardiac death, resuscitated cardiac arrest, or appropriate implantable cardioverter-defibrillator therapy), and an overall composite outcome (first occurrence of any component of the ventricular arrhythmic or heart failure composite end point, all-cause mortality, atrial fibrillation, or stroke). Results: Of the 3282 included patients, 2019 (61.5%) were male, and the mean (SD) age at diagnosis was 47 (15) years. These patients were observed for a median (interquartile range) of 6.8 (3.3-13.3) years. There were 962 patients in the normal weight group (29.3%), 1280 patients in the preobesity group (39.0%), and 1040 patients in the obesity group (31.7%). Patients with obesity were more symptomatic (New York Heart Association class of III/IV: normal weight, 87 [9.0%]; preobesity, 138 [10.8%]; obesity, 215 [20.7%]; P < .001) and more often had obstructive physiology (normal weight, 201 [20.9%]; preobesity, 327 [25.5%]; obesity, 337 [32.4%]; P < .001). At follow-up, obesity was independently associated with the HCM-related overall composite outcome (preobesity vs normal weight: hazard ratio [HR], 1.102; 95% CI, 0.920-1.322; P = .29; obesity vs normal weight: HR, 1.634; 95% CI, 1.332-1.919; P < .001) and the heart failure composite outcome (preobesity vs normal weight: HR, 1.192; 95% CI, 0.930-1.1530; P = .20; obesity vs normal weight: HR, 1.885; 95% CI, 1.485-2.393; P < .001) irrespective of age, sex, left atrium diameter, obstruction, and genetic status. Obesity increased the likelihood of atrial fibrillation but not of life-threatening ventricular arrhythmias. Conclusions and Relevance: Obesity is highly prevalent among patients with HCM and is associated with increased likelihood of obstructive physiology and adverse outcomes. Strategies aimed at preventing obesity and weight increase may play an important role in management and prevention of disease-related complications.

Preemptive Alcohol Septal Ablation to Prevent Left Ventricular Outflow Tract Obstruction after Transseptal Mitral Valve in Valve.

Acute obstruction of the neo-LVOT is a major and potentially fatal complication of transcatheter mitral valve implantation. Patients at high risk of this complication can be identified preoperatively with cardiac CT. We describe a case of a patient identified as high risk for developing neo-LVOT obstruction, who was preemptively treated with alcohol septal ablation prior to successful valve implantation.

Left Ventricular Outflow Tract Obstruction: A Potential Obstacle for Transcatheter Mitral Valve Therapy.

Transcatheter mitral valve replacement is the focus of much enthusiasm as the future of therapy for mitral valve disease. Despite technological advances, left ventricular outflow tract (LVOT) obstruction from the valve prosthesis remains an important issue. In this review the authors discuss the pathophysiology of LVOT obstruction in both the surgical and transcatheter experience, imaging evaluation preprocedure, outcomes to date, and therapeutic options.

Incidence and Risk Factors for Right Ventricular Outflow Tract Obstruction after the Arterial Switch Operation.

BACKGROUND: The aim of this study was to evaluate the incidence and risk factors for the development of right ventricular outflow tract obstruction (RVOTO) after the arterial switch operation (ASO). METHODS: Between 1983 and 2014, a total of 688 patients underwent ASO. RVOTO was defined as any obstruction of the right ventricular outflow tract (RVOT) requiring reintervention. RESULTS: RVOTO developed in 79 patients (11%) at a median time of 3.8 years (range, 1 day-23.6 years) after ASO. Freedom from RVOT reintervention was 96 ± 1, 89 ± 1, and 83 ± 2% at 1, 10, and 25 years, respectively. Independent risk factors for the development of RVOTO in a Cox's regression model were side-by-side great arteries (p < 0.001), aortic arch anomalies (p < 0.001), use of a pericardial patch for augmentation of the coronary buttons (p < 0.001), and a peak gradient more than 20 mm Hg over the RVOT at discharge (p < 0.001). CONCLUSION: The incidence of RVOTO after ASO is not negligible. Complex morphology, such as side-by-side great arteries and aortic arch anomalies influences the development of RVOTO.

Subaortic Stenosis Resection in Children: Emphasis on Recurrence and the Fate of the Aortic Valve.

BACKGROUND: Recurrence after surgical resection of discrete subvalvar aortic stenosis in children often requires repeat operation. Risk factors for recurrence are poorly understood. We sought to determine potential risk factors for recurrence and postoperative comorbidities in the long term. METHODS: Retrospective chart review was performed on all pediatric patients who underwent surgical resection of discrete subaortic stenosis at our institution. Demographics, perioperative findings, and clinical data were analyzed for predisposing factors. RESULTS: From 1991 to 2015, a total of 104 patients underwent primary surgical resection of discrete subaortic stenosis. There were no postoperative deaths. Three (2.9%) patients required pacemaker implantation. Nine (8.4%) patients required repeat resection for recurrence of subaortic membrane over a median follow-up of 8.5 years (interquartile range: 5.9-13.5 years). Actuarial freedom from repeat resection was 100%, 94%, and 82% at one, five, and ten years, respectively. Repeat resection occurred more frequently in patients with genetic disease (37.5% vs 10.7%; P = .033) and preoperative mitral regurgitation (MR; 25% vs 1.2%; P < .001). Postoperative aortic insufficiency (AI) that was moderate or worse was associated with older age at the time of first resection (relative risk [RR]: 1.54, P < .05), moderate or severe preoperative AI (RR: 1.84, P = .002), and repeat resection of subaortic stenosis (RR: 1.90, P < .001). CONCLUSION: The majority of children who undergo surgical resection of subaortic stenosis will not experience recurrence in childhood and those who do require repeat resection may have a higher incidence of genetic disease and preoperative MR. Postoperative AI is associated with repeat resection, older age at the time of surgery, and degree of preoperative AI.

Prediction of ventricular tachyarrhythmia in Brugada syndrome by right ventricular outflow tract conduction delay signs.

BACKGROUND: Brugada syndrome (BrS) is an autosomal dominant disease responsible for sudden cardiac death in young individuals without structural anomalies. The most critical part in the management of this channelopathy is identification of high-risk patients, especially asymptomatic subjects. Prior studies have shown that conduction delay in the right ventricular outflow tract (RVOT) is the main mechanism for developing ventricular tachyarrhythmia (VTA) in BrS patients. The aim of this study was to investigate the significance of electrocardiographic RVOT conduction delay parameters as predictors for development of VTA in patients with BrS. METHODS AND RESULTS: We retrospectively analyzed electrocardiograms obtained from 147 BrS patients (43 ± 15 years, 65% men) and assessed the following electrocardiographic parameters: (1) Tzou criteria (V1R > 0.15 mV, V6S > 0.15 mV, and V6S:R > 0.2), (2) prominent S wave in lead I, lead II, and lead III, (3) SII > SIII, and (4) prominent Q wave in lead III as possible predictors of VTA occurrences during follow-up. Prominent SI, SII, SIII, SII > SIII, QIII, and +ve Tzou criteria occurred more frequently in patients who either presented with VTA or developed VTA during the follow-up of 56 (IQR: 40-76) months. SII > SIII has the highest area under the curve for prediction of VTA (AUC: 0.84, sensitivity: 80%, specificity: 89%). Multivariable regression analysis showed that prominent S waves in lead I, SII > SIII and +ve Tzou criteria are independent predictors for VTA in BrS patients. CONCLUSION: Prominent S in lead I, SII > SIII and +ve Tzou criteria can be used as effective signs for predicting VTA in patients with BrS.

Long-term outcomes of expanded polytetrafluoroethylene conduits with bulging sinuses and a fan-shaped valve in right ventricular outflow tract reconstruction.

OBJECTIVE: Various types of conduits are available for right ventricular outflow tract (RVOT) reconstruction. We have developed an expanded polytetrafluoroethylene (ePTFE) conduit with bulging sinuses and a fan-shaped ePTFE valve. This study summarized the results of a multicenter study evaluating the valved ePTFE conduit. METHODS: The valve functions of 902 patients (median age, 3.9 years; median weight, 12.6 kg) who underwent RVOT reconstruction using valved ePTFE conduits (9 different sizes, 8-24 mm in diameter) at 65 hospitals between 2001 and 2015 were retrospectively investigated. Median follow-up time was 5.5 years. The valve functions were assessed using echocardiography, cardiac catheterization, and magnetic resonance angiography. RESULTS: There were no deaths related to the ePTFE conduit. The peak RVOT gradient was 16.5 ± 13.1 mm Hg, and pulmonary insufficiency graded better than mild was 95.9% at the latest follow-up. Conduit replacement was performed in 55 patients, and in only 3 patients because of conduit infection. Freedom from intervention at 5 years and 10 years was 92.3% and 76.1%, respectively, with small conduits (8-16 mm in diameter) and 99.6% and 95.1%, respectively, with large conduits (18-24 mm in diameter). CONCLUSIONS: The long-term outcomes of the ePTFE conduit with a fan-shaped valve and bulging sinuses appear clinically satisfactory. We believe that the longevity of small-sized conduits can yield sufficient time to exchange them to larger-sized conduits without any loss of their valve functions. Regarding longevity and resistance to infections, this ePTFE valved conduit can be one of the best ways to reconstruct the RVOT.

Standardized Goal-Directed Valsalva Maneuver for Assessment of Inducible Left Ventricular Outflow Tract Obstruction in Hypertrophic Cardiomyopathy.

BACKGROUND: The Valsalva maneuver is widely used to provoke left ventricular outflow tract obstruction in hypertrophic cardiomyopathy (HCM). Whereas early experiments used a standardized, goal-directed approach by maintaining an intraoral pressure >40 mm Hg for >10 sec, current practice depends on patients' understanding and effort. The aim of this study was to evaluate the clinical effectiveness of the goal-directed Valsalva maneuver (GDV) in HCM as a method to provoke left ventricular outflow tract obstruction. METHODS: In this prospective study, patients blew into a syringe barrel connected to a manometer with rubber tubing and maintained an intraoral pressure of >40 mm Hg for >10 sec (GDV). Using Doppler echocardiography, peak left ventricular outflow tract gradient (pLVOTG) was measured at rest and using the provocative maneuvers of the self-directed Valsalva maneuver (SDV), GDV, and exercise. RESULTS: A total of 52 patients were included. Mean pLVOTG with GDV was higher compared with SDV (48 vs 38 mm Hg, P = .001, n = 52) and was similar to exercise (GDV, 52 mm Hg; exercise, 58 mm Hg; P = .42; n = 43). Reclassification to obstructive HCM (pLVOTG ≥ 30 mm Hg) with GDV was significantly higher than with SDV (38% vs 16.6%, P = .016) and comparable with exercise (50%, P = .51). Reclassification to severe obstruction (pLVOTG ≥ 50 mm Hg) was higher with GDV compared with SDV (28.3% vs 13.5%, P = .045) and was similar to exercise (29.7%). Furthermore, GDV identified two patients with occult severe obstruction in isolation. CONCLUSIONS: GDV is an objective, practical, and effective physiologic method of provoking left ventricular outflow tract obstruction. It can significantly alter patient management by reclassifying disease severity and should be incorporated in the routine clinical evaluation of patients with HCM.

Incidence, predictors, and midterm clinical outcomes of left ventricular obstruction after transcatheter aortic valve implantation.

OBJECTIVES: We aimed to evaluate the incidence and midterm clinical outcomes of left ventricular obstruction (LVO) after transcatheter aortic valve implantation (TAVI). BACKGROUNDS: LVO is occasionally unmasked following valve replacement for severe aortic stenosis. However, little is known about the prevalence and effects of LVO after TAVI. METHODS: A total of 158 patients who underwent TAVI in our center between October 2013 and November 2015 received echocardiographic evaluations at baseline; before hospital discharge; and at 3, 6, and 12 months after TAVI. LVO was defined as a peak pressure gradient >30 mm Hg. RESULTS: Over 1 year of follow-up after TAVI, 21 patients (13.3%) demonstrated postprocedural LVO. The incidence was highest at 3-months follow-up and decreased at 6 months or later. Of the 21 patients with LVO, 20 (95.2%) demonstrated midventricular obstruction (MVO), whereas only 1 (4.8%) showed obstruction of the outflow tract (LVOT) with systolic anterior motion (SAM) of the mitral leaflet. In a multivariate analysis, the LVOT diameter (odds ratio [OR], 0.45; 95% confidence interval [CI], 0.30-0.67; P < 0.001), transvalvular velocity (OR, 2.44; 95% CI, 1.13-5.26; P = 0.023), and the presence of accelerated intraventricular flow at baseline (OR, 6.13; 95% CI, 1.49-25.2; P = 0.012) were associated with the occurrence of LVO. Postprocedural LVO was not associated with midterm all-cause death or heart failure events. CONCLUSION: In patients who underwent TAVI, MVO occurred more often than LVOT obstruction. However, the occurrence of postprocedural LVO was not associated with worsened clinical outcomes in these patients.

E/e' ratio and outcome prediction in hypertrophic cardiomyopathy: the influence of outflow tract obstruction.

Aims: Diastolic dysfunction is thought to be an important pathophysiologic component of hypertrophic cardiomyopathy (HCM). However, there are conflicting data on the potential value of the mitral E/e' ratio. We examined whether left ventricular outflow tract (LVOT) obstruction influences the value of E/e' in predicting outcomes in HCM. Methods and results: Patients who met diagnostic criteria for HCM were enrolled. Diastolic function was assessed with complete two-dimensional and Doppler echocardiography. A composite clinical outcome including new onset atrial fibrillation, sustained ventricular tachycardia/fibrillation, heart failure, transplantation, and death was examined over a mean follow-up period of 4.2 years. Among 604 patients, 206 patients had an E/e' level ≥20. Patients with higher septal E/e' level were older, with more severe NYHA class, and more severe LVOT obstruction. Higher E/e' was associated with worse event-free survival in non-obstructive group and total HCM cohort. In addition, E/e' and LVOT pressure gradient were highly correlated in non-obstructive and total HCM, but not in labile or obstructive group. During follow-up period, 95 patients underwent myectomy. Post-op E/e' correlated significantly with LVOT pressure gradient (R = 0.306, P = 0.004). In these patients, post-op E/e' was associated with worse event-free survival (log-rank P = 0.030). Conclusion: Assessment of E/e' is useful for risk stratification in HCM patients. Nevertheless, the predictive power is confounded by dynamic LVOT obstruction. Higher E/e' predicts worse clinical outcomes in non-obstructive HCM and in labile/obstructive after myectomy.

Doppler echocardiography underestimates the prevalence and magnitude of mid-cavity obstruction in patients with symptomatic hypertrophic cardiomyopathy.

OBJECTIVES: To evaluate utility of Doppler echocardiography in the assessment of left ventricular (LV) mid-cavity obstructive (LVMCO) hypertrophic cardiomyopathy (HCM). BACKGROUND: LVMCO is a relatively under-diagnosed complication of HCM and may occur alone or in combination with LV outflow tract obstruction (LVOTO). Identifying and quantifying LVMCO and differentiating it from LVOTO has important implications for patient management. We aimed to assess diagnostic performance of Doppler echocardiography in the assessment of suspected LV obstruction. METHODS: Forty symptomatic HCM patients with suspected obstruction underwent cardiac catheterization, and comparison of location and magnitude of Doppler derived gradients with synchronous invasive measurements (reference standard), at rest and isoprenaline stress (IS). RESULTS: Doppler's diagnostic accuracy for any obstruction (≥30 mmHg) in this cohort was 75% with false positive and false negative rates of 2.5 and 22.5%, respectively. During subanalysis, Doppler's diagnostic accuracy for isolated LVOTO in this selected cohort is 83% with false positive and false negative rates of 4 and 12.5%, respectively. For LVMCO, the accuracy is only 50%, with false positive and false negative rates of 10 and 40%, respectively. Doppler gradients for isolated LVOTO were similar to invasive: 85 ± 51 and 87 ± 35 mmHg, respectively (P = 0.77). Doppler gradients in LVMCO were consistently lower than invasive: 45 ± 38 and 81 ± 31 mmHg, respectively (P = 0.0002). Mid-systolic flow cessation and/or contamination of spectral signals were identified as causes of Doppler-derived inaccuracies. CONCLUSIONS: Doppler echocardiography under-diagnoses and underestimates severity of LVMCO in symptomatic HCM patients. Recognition of abrupt mid-systolic flow cessation and invasive measurements may improve detection of LVMCO in HCM.

Helical distribution of hypertrophy in patients with hypertrophic cardiomyopathy: prevalence and clinical implications.

Recently a novel pattern of helical distribution of hypertrophy has been described in patients with hypertrophic cardiomyopathy (HCM). Our aim was to determine its prevalence and potential implications in an unselected cohort. One-hundred- and eight consecutive patients diagnosed with HCM by cardiac magnetic resonance (CMR) were included (median clinical follow up of 1718 days). All clinical and complementary test information was prospectively collected. The presence of a helical pattern was assessed by a simple measurement of the maximal left ventricle (LV) wall thickness (LVWT) for each of the 17 classical LV segments and it was classified in one of three types according to its extension. A helical distribution was detected in 58% of patients, and was associated to a higher incidence of left ventricular outflow tract obstruction (LVOT; 35% vs. 10%; p = 0.005) and systolic anterior motion of the mitral valve (SAM; 30% vs. 13%, p = 0.053). No significant difference in the maximal LVWT was observed. However, the presence of a helical pattern showed a significant association with non sustained ventricular tachycardia (NSVT; 22% vs. 7%; p = 0.029) and was associated to a higher risk of sudden cardiac death (SCD) calculated with the European society of cardiology (ESC) calculator (p = 0.006). Notably, patients with a more extense spiral had a higher incidence of heart failure (75% vs. 34%, p = 0.012) and all-cause death (21 vs. 3%, p = 0.049). A helical pattern is frequent in HCM and can be readily assessed on CMR standard cine sequences. In conclusion, a helical pattern carries negative clinical implications and is associated to a higher estimated risk of SCD.