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Journal of the American Society of... Jun 2024Latent left ventricular outflow tract obstruction (LVOTO) is an important cause of symptoms in patients with hypertrophic cardiomyopathy (HCM) but can be challenging to...
BACKGROUND
Latent left ventricular outflow tract obstruction (LVOTO) is an important cause of symptoms in patients with hypertrophic cardiomyopathy (HCM) but can be challenging to provoke.
OBJECTIVES AND METHODS
To examine the value of postprandial resting and stress echocardiography and utilization of invasive or enhanced drug therapies (surgical myectomy, alcohol septal ablation, disopyramide and mavacamten) in patients with postprandial LVOTO. Consecutive HCM patients without LVOTO underwent routine and postprandial echocardiography at rest, with provocation (Valsalva and standing) and after symptom-limited treadmill stress.
RESULTS
Among 252 patients (mean age 58 years, 39% women), postprandial LVOT gradients were higher compared with routine echocardiography at rest (median 9.0 [0-38.0] vs 0 [0-14.0] mmHg, p<0.0001) and with provocation (18.5 [0-70.3] vs 1.5 [0-41.0] mmHg, p<0.0001). Postprandial exercise (PPXSE) gradients were higher in a subset of 44 patients who underwent both postprandial and fasting stress echocardiography, (47.0 [5.3-81.0] vs 17.5 [0-46.0] mmHg, p<0.0001). In total, 49 (19.5%) patients achieved the ≥50 mmHg threshold under routine conditions (rest/provocation); 90 (35.7%) additional patients achieved postprandial gradients ≥50 mmHg (rest/provocation/exercise), 38 (15.1%) with PPXSE alone. A total of 71 patients were treated with 91 invasive or enhanced drug therapies, 32 (45.1%) of whom had gradients ≥50 mmHg only after eating (rest/provocation) and 8 (11.3%) only with PPXSE, with symptom relief in the majority.
CONCLUSIONS
Postprandial echocardiography was useful at unmasking LVOTO in more than one third of patients who did not have high gradients otherwise. Eating before echocardiography is a powerful provocative tool in the evaluation of patients with HCM.
PubMed: 38950755
DOI: 10.1016/j.echo.2024.06.011 -
The Journal of Innovations in Cardiac... Jun 2024Transvenous coronary ethanol ablation may be successfully applied to simultaneously treat ventricular arrhythmia superimposed within a segment of hypertrophic...
Simultaneous Ablation of Ventricular Tachycardia and Hemodynamic Improvement of Mid-ventricular Obstructive Hypertrophic Cardiomyopathy by Coronary Venous Ethanol Ablation.
Transvenous coronary ethanol ablation may be successfully applied to simultaneously treat ventricular arrhythmia superimposed within a segment of hypertrophic cardiomyopathy. This presentation nicely describes this emerging technique for ventricular tachycardia ablation and identifies potential additional benefits of venous ethanol administration in patients with left ventricular obstructive physiology.
PubMed: 38948662
DOI: 10.19102/icrm.2024.15062 -
Heart Rhythm Jun 2024Many genetic non-ischemic dilated cardiomyopathies (NICM) cause ventricular tachycardias (VT) originating from scar substrate identified as areas of low electrogram...
BACKGROUND
Many genetic non-ischemic dilated cardiomyopathies (NICM) cause ventricular tachycardias (VT) originating from scar substrate identified as areas of low electrogram voltage. Substrate locations vary and the causes of scar are not well defined.
OBJECTIVE
This study evaluated VT substrate locations in genetic NICM patients undergoing VT ablation to evaluate spatial relationships between specific variants and substrate locations.
METHODS
In this retrospective case series analysis, 32 patients (age 55 +/- 16 years, 94% male, left ventricular ejection fraction 34 +/- 13%) with genetic NICM referred for VT ablation between October 2018 and November 2022 at a single medical center were evaluated. Scar locations were defined as areas of low unipolar/ bipolar voltage.
RESULTS
Of the thirty-two patients evaluated, mutations in TTN (n=11 of 32), LMNA (n=6 of 32), PKP2 (n=5 of 32), MYBPC3 (n=3 of 32), DSP (n=2 of 32), TTR (n=1 of 32), FLNC (n=1 of 32), AGL (n=1 of 32), DES (n=1 of 32), DSG2 (n=1 of 32), were observed. Substrates associated with mutations in TTN were only observed in basal subregions, predominantly anterior (100%), and septal (50%) regions. LMNA mutations were associated with fibrosis in mid inferolateral (60%) and apical inferolateral (60%) regions. Substrate location for individuals with PKP2 mutations were solely observed in the right ventricle, predominantly basal inferolateral regions.
CONCLUSION
Understanding spatial relationships between genetic variants causing NICM and VT substrate locations can help lead to generalizable regions in patients with genetically related NICM presenting in VT which can be investigated during ablation procedures.
PubMed: 38945504
DOI: 10.1016/j.hrthm.2024.06.047 -
Heart Rhythm Jun 2024The concealed nodoventricular/nodofascicular (NV/NF) pathway is mostly a bystander, retrograde bypass tract connecting right ventricle/right bundle branch (RBB) and slow...
BACKGROUND
The concealed nodoventricular/nodofascicular (NV/NF) pathway is mostly a bystander, retrograde bypass tract connecting right ventricle/right bundle branch (RBB) and slow pathway (SP), which is observed in patients with atrioventricular nodal reentrant tachycardia (AVNRT). However, its prevalence and characteristics in response to pacing maneuvers have not been fully evaluated.
OBJECTIVE
This study investigated the prevalence and characteristics of AVNRT with a bystander NV/NF-pathway.
METHODS
We retrospectively reviewed 153 consecutive patients undergoing catheter ablation of AVNRT. Excluding 52 patients with inadequate electrophysiological data, 101 patients composed the study population.
RESULTS
Three patients (3.0%) had bystander concealed NV/NF-pathways, all of which were connected to the SP. The tachycardia was typical SP/fast pathway (FP) AVNRT in two patients and atypical FP/SP AVNRT in one patient. In all cases, His-refractory ventricular extra stimuli (VESs) reset the AVNRTs with delay through the NV/NF-pathways. Ventricular overdrive pacing (VOP) in the early-phase also reset the AVNRT with delay. Earlier VESs and middle-phase of VOP did not reset the tachycardia, and further earlier VESs and late-phase of VOP reset the tachycardia with advance through the RBB-His conduction.
CONCLUSION
A bystander NV/NF-pathway was not rare in patients with AVNRT. The VESs and VOP for the AVNRTs with the bystander NV/NF-pathways were characterized by the two-phase resetting phenomenon: initial transient resetting with delay through the NV/NF-pathway, and late resetting with advance through the RBB-His conduction.
PubMed: 38942105
DOI: 10.1016/j.hrthm.2024.06.049 -
Europace : European Pacing,... Jun 2024Anticoagulation can prevent stroke and prolong lives in patients with atrial fibrillation (AF); However, anticoagulated patients with AF remain at risk of death. The aim...
AIMS
Anticoagulation can prevent stroke and prolong lives in patients with atrial fibrillation (AF); However, anticoagulated patients with AF remain at risk of death. The aim of this study was to investigate the causes of death and factors associated with all-cause and cardiovascular death in the XANTUS population.
METHODS AND RESULTS
Causes of death occurring within a year after rivaroxaban initiation in patients in the XANTUS program studies were adjudicated by a central adjudication committee and classified following international guidance.Baseline characteristics associated with all-cause or cardiovascular death were identified. Of 11,040 patients, 187 (1.7%) died. Almost half of these deaths were due to cardiovascular causes other than bleeding (n = 82, 43.9%), particularly heart failure (n = 38, 20.3%) and sudden or unwitnessed death (n = 24, 12.8%). Fatal stroke (n = 8, 4.3%), which was classified as a type of cardiovascular death, and fatal bleeding (n = 17, 9.1%) were less common causes of death. Independent factors associated with all-cause or cardiovascular death included age, AF type, body mass index, left ventricular ejection fraction, hospitalization at baseline, rivaroxaban dose, and anaemia.
CONCLUSION
The overall risk of death due to stroke or bleeding was low in XANTUS. Anticoagulated patients with AF remain at risk of death due to heart failure and sudden death. Potential interventions to reduce cardiovascular deaths in anticoagulated patients with AF, require further investigation, e.g. early rhythm control therapy and AF ablation.
PubMed: 38941511
DOI: 10.1093/europace/euae183 -
Circulation. Arrhythmia and... Jun 2024
PubMed: 38939957
DOI: 10.1161/CIRCEP.124.012915 -
JACC. Advances Jan 2024Multilevel obstruction in left ventricular inflow and outflow predisposes to arrhythmias in Shone's complex (SC).
BACKGROUND
Multilevel obstruction in left ventricular inflow and outflow predisposes to arrhythmias in Shone's complex (SC).
OBJECTIVES
The purpose of this study was to study the prevalence and outcomes (heart failure [HF] hospitalization, cardiac transplant, death) of cardiac arrhythmias in adults with SC.
METHODS
Adults with SC (defined as ≥2 lesions out of supramitral ring, parachute mitral valve, subvalvular/valvular aortic stenosis (AS), and aortic coarctation) seen at Mayo Clinic between January 1999 and March 2020 were identified and evaluated for the presence of sustained atrial fibrillation, atrial flutter, and ventricular arrhythmias (VA). Kaplan-Meier survival analysis was used to calculate the occurrence of these arrhythmias.
RESULTS
Seventy-three patients with SC (mean age at first visit 33 ± 13 years) were identified. Most common anomalies were valvular AS (88%), coarctation (85%), parachute mitral valve (44%), subvalvular AS (44%), and supramitral ring (25%). Atrial arrhythmias were diagnosed in 24 patients (33%) at a mean age of 34.6 ± 12.7 years. Patients with atrial fibrillation and atrial flutter had higher number of surgeries, left atrial size, right ventricular systolic pressure, and HF hospitalizations. A rhythm control approach was used in majority of patients (75% on antiarrhythmic drugs and 50% underwent catheter ablation). Sustained VA occurred in 6 of 73 patients of whom 4 had an ejection fraction <40%. Death and cardiac transplantation occurred in 11 and 3 patients, respectively, during a median follow-up of 7.3 ± 6.0 years.
CONCLUSIONS
In adults with SC, atrial arrhythmias occurred in one-third of patients, were associated with more HF hospitalizations, and frequently required rhythm control. Prevalence of sustained VA was 8% and implantable cardioverter-defibrillator implantation should be considered in those with reduced ejection fraction.
PubMed: 38939811
DOI: 10.1016/j.jacadv.2023.100715 -
Journal of Arrhythmia Jun 2024Intraoperative ventricular tachycardia (VT) ablation targeting the epicardial substrate using three-dimensional electroanatomic mapping (EAM) was performed during left...
Intraoperative ventricular tachycardia (VT) ablation targeting the epicardial substrate using three-dimensional electroanatomic mapping (EAM) was performed during left ventricular assist device (LVAD) implantation. We proved that EAM can be safely performed during LVAD implantation and that an ablation strategy based on electrophysiological information may reduce VT recurrence after LVAD implantation.
PubMed: 38939782
DOI: 10.1002/joa3.13029 -
Journal of Arrhythmia Jun 2024Electrocardiography and 3D mapping images of the case.
Electrocardiography and 3D mapping images of the case.
PubMed: 38939761
DOI: 10.1002/joa3.13022 -
Journal of Applied Physiology... Jun 2024In a 77-year-old former world-record holding male marathoner (2:08:33.6) this study sought to investigate the impact of lifelong intensive endurance exercise on cardiac...
In a 77-year-old former world-record holding male marathoner (2:08:33.6) this study sought to investigate the impact of lifelong intensive endurance exercise on cardiac structure, function and the trajectory of functional capacity (determined by maximal oxygen consumption, V̇Omax) throughout the adult lifespan. As a competitive runner, our athlete (DC) reported performing up to 150-300 miles/wk of moderate-to-vigorous exercise, and sustained 10-15 hours/wk of endurance exercise after retirement from competition. DC underwent maximal cardiopulmonary exercise testing in 1970 (aged 27yrs), 1991 (aged 49yrs) and 2020 (aged 77yrs) to determine V̇Omax. At his evaluation in 2020, DC also underwent comprehensive cardiac assessments including resting echocardiography, and resting and exercise cardiac magnetic resonance to quantify cardiac structure and function at rest and during peak supine exercise. DC's V̇Omax showed minimal change from 27yrs (69.7mL/kg/min) to 49yrs (68.1mL/kg/min), although it eventually declined by 36% by the age of 77yrs (43.6mL/kg/min). DC's V̇Omax at 77yrs, was equivalent to the 50 percentile for healthy 20-29 year-old males and 2.4 times the requirement for maintaining functional independence. This was partly due to marked ventricular dilatation (left-ventricular end-diastolic volume: 273mLs), which facilitates a large peak supine exercise stroke volume (200mLs) and cardiac output (22.2L/min). However, at the age of 78 years, DC developed palpitations and fatigue, and was found to be in atrial fibrillation requiring ablation procedures to revert his heart to sinus rhythm. Overall, this life study of a world champion marathon runner exemplifies the substantial benefits and potential side effects of many decades of intense endurance exercise.
PubMed: 38935800
DOI: 10.1152/japplphysiol.00070.2024