Left Ventricular Outflow Obstruction Research Articles

Long-Term Outcome of Mustard/Senning Correction for Transposition of the Great Arteries in Sweden and Denmark.

The atrial switch operation, the Mustard or Senning operation, for the transposition of the great arteries (TGA) was introduced in the late 1950s and was the preferred surgery for TGA until the early 1990s. The Mustard and Senning operation involves extensive surgery in the atria and leaves the right ventricle as the systemic ventricle. The Mustard and Senning cohort is now well into adulthood and we begin to see the long-term outcome. All the 6 surgical centers that performed Mustard and Senning operations in Sweden and Denmark identified all operated TGA patients. Information about death was obtained in late 2007 and early 2008 from the Danish and Swedish Centralised Civil Register by using the patients' unique national Civil Registration Numbers. Four hundred sixty-eight patients undergoing the atrial switch operation were identified. Perioperative 30-day mortality was 20%, and 60% were alive after 30 years of follow-up. Perioperative mortality was significantly increased by the presence of a ventricular septal defect, left ventricular outflow obstruction, surgery early in the Mustard and Senning era. However, only pacemaker implantation is predictive of long-term outcome (hazard ratio, 1.90; 95% confidence interval, 1.05-3.46, P=0.04), once the TGA patient has survived the perioperative period. The risk of reoperation was correlated to the presence of associated defects and where the first Mustard/Senning operation was performed. The long-term survival of patients with Mustard and Senning correction for TGA appears to be primarily determined by factors in the right ventricle and tricuspid valve and not the timing of or the type of surgery in childhood. Cardiac function necessitating the implantation of a pacemaker is associated with an increase in mortality.

An unusual cause of dynamic left ventricular outflow obstruction: An unusual case of dynamic LVOTO

This lady has a known history of Ebstein's anomaly. She presented with a history of increasing dyspnea on exertion and an episode of syncope. An ECG and holter monitoring were unremarkable. Given her known history of Ebstein's anomaly, she proceeded to CMR imaging.

Clinical Characteristics and Outcome of Alcohol Septal Ablation With Confirmation by Nitroglycerin Test for Drug-Refractory Hypertrophic Obstructive Cardiomyopathy With Labile Left Ventricular Outflow Obstruction

Careful evaluation, including provocation tests, is needed to specify an indication for septal reduction therapy in patients with drug-refractory hypertrophic obstructive cardiomyopathy. This study aimed to evaluate the outcome of alcohol septal ablation (ASA) using an intravenous nitroglycerin test (IV-NTG). Of consecutive 156 patients, after excluding cases of severe valvular disease and repeat septal reduction therapy, we investigated the clinical characteristics of patients with labile obstruction (n = 32) and the outcomes after ASA using the IV-NTG test; comparisons were made with those exhibiting basal obstruction (a resting gradient of ≥30 mm Hg). The patients with labile obstruction had less left ventricular mass (141 ± 47 vs 182 ± 59 g, p = 0.003) and less brain natriuretic peptide values (414 ± 576 vs 744 ± 625 pg/ml, p <0.001) than those with basal obstruction. Immediately after ASA, the gradients improved from 15 ± 7 to 5 ± 5 mm Hg and the IV-NTG-provoked gradients improved from 74 ± 25 to 13 ± 9 mm Hg, respectively. At 1-year follow-up, the New York Heart Association functional class had improved from 2.7 ± 0.5 to 1.3 ± 0.5. There was no sudden cardiac death during the follow-up period (5.1 ± 3.0 years), and 8-year survival free from cardiovascular death was 94%. In conclusion, patients with labile obstruction had less-severe left ventricular hypertrophy but exhibited symptoms comparable to those with basal obstruction. The IV-NTG test is a useful method for rapidly confirming acute reduction of the latent gradient after the ASA procedure, and the outcome of ASA for labile obstruction was favorable.

Galectin-3 levels in patients with hypertrophic cardiomyopathy and its relationship with left ventricular mass index and function.

Objective:Cardiac fibrosis is an important contributor to adverse left ventricular (LV) remodeling and arrhythmias in patients with hypertrophic cardiomyopathy (HCM). Galectin-3 (Gal-3) is a novel marker of cardiac fibrosis and inflammation. In this study, we investigated Gal-3 levels in patients with HCM and controls and assessed the relationship between Gal-3 level and echocardiographic indices using strain echocardiography in patients with HCM.Methods:Forty patients with HCM in sinus rhythm and 35 healthy controls were prospectively enrolled in this case-control study. The HCM diagnosis was based on two-dimensional echocardiographic demonstration of a hypertrophied and non-dilated left ventricle (LV) with a wall thickness ≥15 mm in one or more LV myocardial segments in the absence of any cardiac or systemic disease capable of inducing LV hypertrophy. Patients with one of the followings were excluded: coronary artery disease, atrial fibrillation episodes on 24-h Holter electrocardiogram (ECG) monitoring, history of an invasive intervention to alleviate an LV outflow (LVOT) obstruction, inadequate image quality, renal disease, diabetes mellitus, hyperlipidemia, liver cirrhosis, and pulmonary fibrosis. Global LV longitudinal, circumferential strain and strain rates, peak torsion, and LV mass index (LVMI) of all subjects were assessed by echocardiography. Gal-3 levels were measured in all subjects.Results:Left ventricular global longitudinal strain (-13.37±4.6% vs. -18.93±2.5%, p<0.001) and strain rate (0.66±0.22 s-1 vs. 1.08±0.14 s-1, respectively; p<0.001) values were lower in patients with HCM than in controls. Gal-3 levels were significantly higher in patients with HCM than in controls (16.9±6.64 ng/mL vs. 13.21±3.42 ng/mL, p=0.005). Gal-3 levels were associated with the thickness of the interventricular septum (r=0.444, p=0.004) and LVMI (r=0.365, p=0.021); however, they were not associated with LV global longitudinal strain (p=0.42) or strain rate (p=0.28).Conclusion:Gal-3 levels increased and were correlated with the degree of LV hypertrophy in patients with HCM. Gal-3 is not a good marker of decreased myocardial LV diastolic and systolic functions in these patients.

Left ventricular outflow obstruction secondary to accessory mitral valve tissue in a patient with hypertrophic cardiomyopathy.

Left ventricular outflow obstruction secondary to accessory mitral valve tissue in a patient with hypertrophic cardiomyopathy.

Long-term outcomes after surgical repair of complete atrioventricular septal defect

ObjectiveSurvival after surgical repair for complete atrioventricular septal defect (CAVSD) has improved, but patients are at risk for reoperation to address left atrioventricular valve regurgitation and left ventricular outflow tract obstruction. We examined the long-term survival, need for reoperation, and associated risk factors after CAVSD repair at our institution. MethodsBetween 1974 and 2000, a total of 198 patients underwent surgical repair for CAVSD. Of these, 178 patients survived to hospital discharge, of whom 153 (86%) had available follow-up data at a median postoperative time point of 17.2 years (range: 2 months to 38.1 years). ResultsOverall perioperative mortality was 10.1%, with a significant decrease to 2.9% in the late surgical era: 1991 to 2000 (P < .001). The overall estimated survival for the entire cohort was 85% at 10 years, 82% at 20 years, and 71% at 30 years after initial CAVSD repair. Requiring a reoperation after initial CAVSD repair was a risk factor for late mortality (P = .04). The estimated freedom from reoperation was 88% at 10 years, 83% at 20 years, and 78% at 30 years after initial CAVSD repair. Indications for reoperation included left atrioventricular valve regurgitation in 14 patients (7.1%) and left ventricular outflow obstruction in 7 patients (3.5%). ConclusionsLong-term survival after repair of CAVSD remains good. However, the need for reoperation is common and affects long-term survival after CAVSD repair.

Hypertensive heart disease and bronchodilators: Potential left ventricular outflow obstruction

Hypertensive heart disease and bronchodilators: Potential left ventricular outflow obstruction

Surgical Considerations in d-Transposition of the Great Arteries.

The surgical treatment for d-transposition has evolved dramatically since the inception of cardiac surgery in the 1950s. Today, the arterial switch operation is employed almost exclusively in the management of this disease unless significant left ventricular outflow obstruction is present. Surgical options for these patents are reviewed and an in-depth technical discussion of arterial switch for d-transposition of the great arteries/intact ventricular septum follows.

Targeted Mybpc3 Knock-Out Mice with Cardiac Hypertrophy Exhibit Structural Mitral Valve Abnormalities.

MYBPC3 mutations cause hypertrophic cardiomyopathy, which is frequently associated with mitral valve (MV) pathology. We reasoned that increased MV size is caused by localized growth factors with paracrine effects. We used high-resolution echocardiography to compare Mybpc3-null, heterozygous, and wild-type mice (n = 84, aged 3–6 months) and micro-CT for MV volume (n = 6, age 6 months). Mybpc3-null mice showed left ventricular hypertrophy, dilation, and systolic dysfunction compared to heterozygous and wild-type mice, but no systolic anterior motion of the MV or left ventricular outflow obstruction. Compared to wild-type mice, echocardiographic anterior leaflet length (adjusted for left ventricular size) was greatest in Mybpc3-null mice (1.92 ± 0.08 vs. 1.72 ± 0.08 mm, p < 0.001), as was combined leaflet thickness (0.23 ± 0.04 vs. 0.15 ± 0.02 mm, p < 0.001). Micro-CT analyses of Mybpc3-null mice demonstrated increased MV volume (0.47 ± 0.06 vs. 0.15 ± 0.06 mm3, p = 0.018) and thickness (0.35 ± 0.04 vs. 0.12 ± 0.04 mm, p = 0.002), coincident with increased markers of TGFβ activity compared to heterozygous and wild-type littermates. Similarly, excised MV from a patient with MYBPC3 mutation showed increased TGFβ activity. We conclude that MYBPC3 deficiency causes hypertrophic cardiomyopathy with increased MV leaflet length and thickness despite the absence of left ventricular outflow-tract obstruction, in parallel with increased TGFβ activity. MV changes in hypertrophic cardiomyopathy may be due to paracrine effects, which represent targets for therapeutic studies.

Evidence of Myocardial Edema in Obstructive Tako-tsubo Cardiomyopathy Complicated by Cardiogenic Shock

the contemporary presence of left ventricular (LV) outflow tract obstruction, systolic anterior motion of the anterior mitral leaflet, and acute mitral regurgitation may occur in t ako-tsubo cardiomyopathy. Although myocardial edema has been reported in patients with tako-tsubo cardiomyopathy, to the best of our knowledge it has never been described in the setting of LV outflow obstruction and the presence of cardiogenic shock. We report the case of a 65-year-old woman who developed t ako-tsubo cardiomyopathy followed by acute cardiogenic shock. the echo-Doppler assessment revealed LV apical ballooning, moderate-to-severe mitral regurgitation, and an estimated peak systolic pressure gradient at LV outflow tract of 64 mmHg. the LV outflow obstruction and mitral regurgitation resolved shortly after the intravenous administration of atenolol (1.25 mg). the cardiogenic shock was completely resolved following the infusion of low-dose dobutamine: 2 γ/kg/min. In the following days, an echo-Doppler examination revealed a marked reduction in the thickness of the LV proximal hypertrophied septum (from 20 mm to 14 mm), while a cardiac magnetic resonance imaging study showed signs of mild edema of the mid-ventricular and apical septum.

Hypertrophic cardiomyopathy: a review.

Hypertrophic cardiomyopathy (HCM) is a relatively common disorder that anesthesiologists encounter among patients in the perioperative period. Fifty years ago, HCM was thought to be an obscure disease. Today, however, our understanding and ability to diagnose patients with HCM have improved dramatically. Patients with HCM have genotypic and phenotypic variability. Indeed, a subgroup of these patients exhibits the HCM genotype but not the phenotype (left ventricular hypertrophy). There are a number of treatment modalities for these patients, including pharmacotherapy to control symptoms, implantable cardiac defibrillators to manage malignant arrhythmias, and surgical myectomy and septal ablation to decrease the left ventricular outflow obstruction. Accurate diagnosis is vital for the perioperative management of these patients. Diagnosis is most often made using echocardiographic assessment of left ventricular hypertrophy, left ventricular outflow tract gradients, systolic and diastolic function, and mitral valve anatomy and function. Cardiac magnetic resonance imaging also has a diagnostic role by determining the extent and location of left ventricular hypertrophy and the anatomic abnormalities of the mitral valve and papillary muscles. In this review on hypertrophic cardiomyopathy for the noncardiac anesthesiologist, we discuss the clinical presentation and genetic mutations associated with HCM, the critical role of echocardiography in the diagnosis and the assessment of surgical interventions, and the perioperative management of patients with HCM undergoing noncardiac surgery and management of the parturient with HCM.

Surgical management of left ventricular outflow obstruction in hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy is the single most common form of inherited heart disease. Left ventricular outflow tract obstruction (LVOTO) is a recognised feature of this condition which arises when blood leaving the outflow tract is impeded by systolic anterior motion of the mitral valve. In an important minority of patients, breathlessness, chest pain and syncope may result and persist despite the use of medications. In suitable candidates, surgery may relieve obstruction and its associated symptoms, and normalise life expectancy. Refinements in surgical techniques have marked improvements in the understanding of mechanisms underlying LVOTO. In this review, we hope to provide the reader with an understanding of how contemporary surgical practice has developed, which patients should be considered for surgery, and what results are anticipated. The role echocardiography plays in this area is highlighted throughout.

Clinical Outcomes of Mitral Valve Replacement With the 16-mm ATS Advanced Performance Valve in Neonates and Infants

Although mitral valve repair is the preferred treatment for mitral regurgitation in neonates and infants, mitral valve replacement (MVR) is sometimes necessary. From 1999 through 2013, 18 patients younger than 1 year underwent MVR with the smallest (16 mm) commercially available mechanical valve. At surgery, mean age was 4.0 ± 1.8 months (range, 4 days to 7 months), and mean body weight was 5.3 ± 1.6 kg (range, 3.2 to 8.3 kg). Prosthetic valves were implanted in the supra-annular position in 17 of the 18 patients. All patients were followed up, and the mean follow-up period was 4.5 ± 3.8 years (range, 0.2 to 14 years). The rates of overall survival and freedom from redo MVR at 10 years were 88.9% and 57.8%, respectively. The causes of redo MVR were pulmonary hypertension in patients with left ventricular outflow obstruction (n = 2), hemolysis (n = 1), and a stuck valve (n = 1). The estimated effective orifice area index (effective orifice area/body surface area) was significantly inversely correlated with peak transmitral pressure gradient (r = -0.784, p < 0.01). The rate of freedom from permanent pacemaker implantation at 10 years was 71.2%. Three of the 5 pacemaker implantation procedures were for postoperative sick sinus syndrome. Although intracranial hemorrhage developed in 3 infants, all neurologic sequelae resolved. The implanted valves were durable, and no premature increase in transmitral pressure gradient was observed. Complications included injury of the sinus node artery and hemorrhage related to anticoagulation therapy.

Efficacy and safety of the angiotensin II receptor blocker losartan for hypertrophic cardiomyopathy: the INHERIT randomised, double-blind, placebo-controlled trial

No medical treatment has been reliably shown to halt or reverse disease progression in hypertrophic cardiomyopathy, but the results of several pilot studies have suggested beneficial effects of angiotensin II receptor blockers on left ventricular hypertrophy and fibrosis, which are predictive of an adverse outcome. We aimed to assess the effect of the angiotensin II receptor blocker losartan on left ventricular hypertrophy and fibrosis in patients with hypertrophic cardiomyopathy. In this single-centre, randomised, double-blind, placebo-controlled trial, adult patients (aged 18 years and older) with obstructive or non-obstructive hypertrophic cardiomyopathy were randomly assigned via computer-based system to losartan (100 mg per day) or placebo for 12 months. Patients and investigators were masked to assigned treatment. The primary endpoint was change in left ventricular mass as assessed by cardiac magnetic resonance imaging (CMR) or CT. Efficacy analyses were done in the modified intention-to-treat population (all patients with data available at the 12-month follow-up). The trial is registered with ClinicalTrials.gov, number NCT01447654. Between Dec 1, 2011, and May 1, 2013, 318 patients were screened. 133 patients (mean age 52 years [SD 13], 35% women) consented and were randomly assigned to placebo (n=69) or losartan (n=64). 124 (93%) patients completed the study and were included in the modified intention-to-treat analysis for the primary endpoint. After 12 months we noted no significant difference in the change in left ventricular mass between the placebo group and the losartan group (mean difference 1 g/m(2), 95% CI -3 to 6; p=0·60). A decrease in systolic blood pressure in the losartan group (from mean 127 mm Hg [SD 12] to 121 mm Hg [14]; p=0·0001) confirmed drug compliance; blood pressure did not decrease in the placebo group. Two (2%) patients, both in the placebo group, died from sudden cardiac death during follow-up. In the losartan group, one (1%) patient had angioedema, one (1%) had deterioration of renal function, and one (1%) had hyperkalaemia. Treatment was well tolerated by patients with left ventricular outflow obstruction at baseline. Our findings challenge the generally held view that angiotensin II receptor blockers reduce cardiac hypertrophy. Treatment with losartan was safe, suggesting that it can be used for other indications in patients with hypertrophic cardiomyopathy, irrespective of obstructive physiology. Additional studies are needed to assess the effect of angiotensin II receptor blockers in preclinical hypertrophic cardiomyopathy-eg, in genotype-positive but phenotype-negative individuals.

Clinical Profile of Hypertrophic Cardiomyopathy in a Tertiary Level Hospital

Background- Hypertrophic cardiomyopathy (HCM) is a genetically transmitted disease with diverse natural history for which the potential to produce adverse consequences has been emphasized. However, the possibility of this disease remaining clinically dormant for many years has not been as widely appreciated. Certainly, the clinical recognition of previously undiagnosed patients with HCM may be advantageous by permitting risk stratification for sudden cardiac death or for timely pharmacologic therapy when symptoms intervene. The purpose of this study was to assess the disease pattern and the extent to which hypertrophic cardiomyopathy (HCM) exists undetected in a suspected group of population never diagnosed to have any cardiovascular disease, referred from the primary care facilities to one of the largest tertiary level hospital of Bangladesh. Methods-We prospectively conducted an echocardiographic survey in 3648 cases between 19-03-2009 to 03-08-2010 (18 months) in the cardiac centre of Combined Military Hospital, Dhaka, Bangladesh. Results- A total of 3648 cases referred by primary care physicians underwent echocardiogram either to confirm a new diagnosis or to exclude obvious cardiovascular abnormalities. Hypertrophic cardiomyopathy was identified in 148 patients (4.06%) who was not known have any cardiac disease before. At diagnosis, age ranged from 20 to 83 years (mean 52.19) with male gender preponderance (85.81%). Ninety eight patients (67%) had no functional limitation and the remaining fifty patients reported with symptoms mostly giving multiple responses like chest pain (39.2%), palpitation (18.9%), dyspnoea (22.3%), unusual fatigability (16.9%) and syncope (6.8%). Twelve patients had strong suspicion of familial predisposition depending on the symptomatology of the familial tree but were confirmed only in 03 cases by echocardiography. Basal left ventricular outflow obstruction (gradients 20 to 76 mm Hg) was evident in 14 patients (9.45%). Relatively variable phenotypic expression of the disease was substantiated by diffuse thickening of left ventricular wall occurring more commonly than localized distributed hypertrophy (56.08% vs. 43.94%, respectively). Electrocardiogram was abnormal in almost 95% of cases and typical pattern of left ventricular hypertrophy was observed in 25.68% cases. Conclusion -This prospectively assembled data show that HCM cases may remain asymptomatic, clinically dormant and undetectable for many years (often to advance ages) in our community. The actual prevalence of the disease in our community needs to be ascertained which might exceed the prevalence mentioned in the text books. DOI: http://dx.doi.org/10.3329/cardio.v7i1.20798 Cardiovasc. j. 2014; 7(1): 31-37

Surgical septal myectomy versus alcohol septal ablation: assessing the status of the controversy in 2014.

In hypertrophic cardiomyopathy (HCM), left ventricular (LV) outflow tract obstruction, caused by mitral valve systolic anterior motion (SAM) with elevated intracavitary LV pressures, can produce disabling symptoms of heart failure and excess cardiovascular mortality.1–7 Outflow gradients are common in HCM, present in 70% of patients at rest or with physiological exercise4 (Figure 1). Fifty years ago, early HCM investigators recognized the importance of obliterating LV outflow obstruction (and mitral regurgitation) and restoring normal hemodynamics, initially with the septal myectomy operation advanced by Dr Andrew Morrow at the National Institutes of Health.6,7 However, HCM has not been immune to controversy, and through the years, several debates have focused on the significance of dynamic outflow obstruction and its treatment.7 The most recent of these conversations concerns the most effective strategy for reducing gradient and symptoms, triggered by the introduction of catheter-based percutaneous alcohol septal ablation (ASA) as an alternative to myectomy.8–19 Figure 1. Treatment algorithm for hypertrophic cardiomyopathy (HCM) patients with heart failure symptoms of exertional dyspnea with or without chest pain. LVOT indicates left ventricular outflow tract; and NYHA, New York Heart Association. The nonsurgical technique, introduced by Professor Ulrich Sigwart at the Royal Brompton Hospital in 1994,8 involves injection of 1 to 4 mL of 96% ethanol into the first septal perforator branch of the left anterior descending coronary artery to produce a basal septal myocardial infarction and ultimately remodeling of the LV outflow tract. ASA avoids the recovery time with loss of work, residual discomfort, and anxiety associated with surgery. It was soon enthusiastically embraced and heavily promoted by many clinicians and interventional cardiologists, initially in Europe, thereby expanding the treatment armamentarium of HCM and triggering a polarized and sometimes contentious debate within the cardiovascular community. Indeed, many related …

Hybrid palliation for critical systemic outflow obstruction: Neither rapid stage 1 Norwood nor comprehensive stage 2 mitigate consequences of early risk factors

Hybrid palliation with branch pulmonary artery banding (bPAB) has become increasingly common in the early management of patients with critical left ventricular outflow obstruction. Optimal subsequent surgical palliation remains undefined. We retrospectively reviewed patients undergoing initial bPAB for single ventricle physiology with systemic outflow obstruction (2001-2013, n=37). Patients were stratified by subsequent surgical palliation: stage 1 Norwood (St1N, n=14), comprehensive stage 2 (CompSt2, n=11), and none (n=12). bPAB was performed at a median of 4 days and 2.7-kg, post-bPAB mortality was increased in patients with aortic atresia (odds ratio [OR]=3.8, 95% confidence interval [CI]=0.9-15.8) or birth weight <2 kg (OR=13.8, 95% CI=1.4-136.4). Palliation strategy did not affect transplant-free survival through second-stage palliation (St1N: 71.4%, CompSt2: 72.7%, P=.9). Among CompSt2 patients, there was a trend toward poorer survival with aortic atresia (0% vs 80%, P=.09); birth weight <2.5 kg was associated with decreased survival (0% vs 89.0%, P=.01). A trend toward lower survival with low birth weight was evident among St1N patients (<2 kg, OR=0.1, 95% CI=0.01-1.9, P=.09). CompSt2 mortality occurred on postoperative days 0 and 1. Mortality following St1N occurred at a median of 38.5 days (range=23.5-104.5). Among survivors of stage 2 palliation, Fontan completion was performed in the same number of patients in each group (St1N: 6/8, 75%, CompSt2: 6/8, 75%). Both St1N and CompSt2 are viable options for subsequent palliation following initial hybrid procedure. Transplant-free survival and eventual Fontan candidacy are similar between groups. Delaying surgical palliation with the CompSt2 did not mitigate the impact of early risk factors such as low birth weight and aortic atresia.

Atrioventricular Node Reentrant Tachycardia as a Cause of Recurrent Syncope in a Patient With Non-obstructive Hypertrophic Cardiomyopathy

A 60-year-old male patient was admitted to our hospital for recurrent syncope. On arrival at our hospital, the patient was totally oriented. Blood pressure was 180/104mmHg, with a heart rate of 100bpm. ECG showed high voltage of precordial leads and minor ST-segment depression in lateral leads. Echocardiography demonstrated preserved left ventricular (LV) systolic function and asymmetrical ventricular wall hypertrophy. LV outflow obstruction was undetectable. Cardiac MRI demonstrated late gadolinium enhancement in the hypertrophied anteroseptal wall. Together, the patient was diagnosed as non-obstructive hypertrophic cardiomyopathy (HCM). During the hospital stay, 24-h Holter monitoring was conducted, demonstrating no pauses and no ventricular tachy-arrhythmias. Both head-up-tilt test and head MRI showed no abnormal findings. On electrophysiological studies, ventricular tachycardia was not induced by extra-stimuli and basic drives from the right ventricle.However, atrioventricular node reentrant tachycardia (AVNRT) was induced by extra-stimuli of the right atrium, which resulted in sudden decrease of systolic blood pressure from 120mmHg to 50mmHg and presyncope. Subsequently, catheter ablation to the slow pathway was successfully performed, after which the patient have not suffered from syncope. HCM patients with one or more recent episodes of unexplained syncope meet indications for ICD (class IIa). Unnecessary ICD implantation in this patient was avoided by a prompt diagnosis of AVNRT, which is an uncommon cause of syncope in non-obstructive HCM. A 60-year-old male patient was admitted to our hospital for recurrent syncope. On arrival at our hospital, the patient was totally oriented. Blood pressure was 180/104mmHg, with a heart rate of 100bpm. ECG showed high voltage of precordial leads and minor ST-segment depression in lateral leads. Echocardiography demonstrated preserved left ventricular (LV) systolic function and asymmetrical ventricular wall hypertrophy. LV outflow obstruction was undetectable. Cardiac MRI demonstrated late gadolinium enhancement in the hypertrophied anteroseptal wall. Together, the patient was diagnosed as non-obstructive hypertrophic cardiomyopathy (HCM). During the hospital stay, 24-h Holter monitoring was conducted, demonstrating no pauses and no ventricular tachy-arrhythmias. Both head-up-tilt test and head MRI showed no abnormal findings. On electrophysiological studies, ventricular tachycardia was not induced by extra-stimuli and basic drives from the right ventricle. However, atrioventricular node reentrant tachycardia (AVNRT) was induced by extra-stimuli of the right atrium, which resulted in sudden decrease of systolic blood pressure from 120mmHg to 50mmHg and presyncope. Subsequently, catheter ablation to the slow pathway was successfully performed, after which the patient have not suffered from syncope. HCM patients with one or more recent episodes of unexplained syncope meet indications for ICD (class IIa). Unnecessary ICD implantation in this patient was avoided by a prompt diagnosis of AVNRT, which is an uncommon cause of syncope in non-obstructive HCM.

The Case Files

The Case Files

Need for a standardized protocol for stress echocardiography in provoking subaortic and valvular gradient in various cardiac conditions.

(Semi) supine exercise testing has an established role in the evaluation of patients with valvular heart disease and can help clinical decision making. Stress echocardiography has the advantages of its wide availability, low cost, and versatility for the assessment of disease severity. However, exercise-induced changes in valve hemodynamics, left ventricular outflow obstruction and pulmonary artery pressure depended on load variation. Changing position from supine to upright rapidly decreases load conditions for the ventricles. Therefore several cardiac centers have proposed exercise stress echocardiography in the upright position with gradient monitoring sometimes also in post-exercise recovery. Doppler measurement of subaortic gradient has been a very helpful and informative examination in several heart diseases (especially in hypertrophic cardiomyopathy, valve heart diseases, prosthesis dysfunction).