Impact of Surgical and Transcatheter Aortic Valve Replacement on Frailty Score.

OBJECTIVE: Frailty is common in the aortic stenosis (AS) population and impacts outcomes after both transcatheter and surgical aortic valve replacement (TAVR and sAVR, respectively). Frailty can significantly impact the decision regarding the suitability of a patient for aortic valve intervention, with frail patients often excluded. Since many frailty tools use indicators which may be influenced by AS itself, some of which are subjectively symptom driven, we sought to determine the impact of intervention on frailty scores. METHODS: A prospective, observational cohort study included patients being assessed for aortic valve (AV) intervention with either TAVR or sAVR due to severe aortic stenosis. Patients were assessed for symptoms at baseline, and 1- and 6-months post intervention subjectively, using the New York Heart Association (NYHA) class and the Kansas City Cardiomyopathy Questionnaire (KCCQ), and objectively, using a 6-minute walk test (6MWT). These were compared with frailty at baseline and final review using the Fried Frailty Scale (FFS). RESULTS AND CONCLUSIONS: Sixty-six (66) patients completed pre- and post-intervention reviews. The mean FFS score was significantly lower, indicating less frailty, at 6 months relative to pre procedure (1.18 vs 1.73, p=0.002). This correlated with the change in symptoms (p<0.001). Between intervention groups, the final mean FFS of both groups decreased significantly, with TAVR to 1.33 (p=0.030) and sAVR to 0.8 (p=0.015). There was no difference in the degree of improvement between interventions (p=0.517). Aortic valve intervention improves frailty scores in both TAVR and sAVR treated patients.

Atrial fibrosis and substrate based characterization in atrial fibrillation: Time to move forwards.

Atrial fibrillation (AF) is the most commonly encountered cardiac arrhythmia in clinical practice. However, current therapeutic interventions for atrial fibrillation have limited clinical efficacy as a consequence of major knowledge gaps in the mechanisms sustaining atrial fibrillation. From a mechanistic perspective, there is increasing evidence that atrial fibrosis plays a central role in the maintenance and perpetuation of atrial fibrillation. Electrophysiologically, atrial fibrosis results in alterations in conduction velocity, cellular refractoriness, and produces conduction block promoting meandering, unstable wavelets and micro-reentrant circuits. Clinically, atrial fibrosis has also linked to poor clinical outcomes including AF-related thromboembolic complications and arrhythmia recurrences post catheter ablation. In this article, we review the pathophysiology behind the formation of fibrosis as AF progresses, the role of fibrosis in arrhythmogenesis, surrogate markers for detection of fibrosis using cardiac magnetic resonance imaging, echocardiography and electroanatomic mapping, along with their respective limitations. We then proceed to review the current evidence behind therapeutic interventions targeting atrial fibrosis, including drugs and substrate-based catheter ablation therapies followed by the potential future use of electro phenotyping for AF characterization to overcome the limitations of contemporary substrate-based methodologies.

Transcatheter Transseptal Mitral Valve-in-Valve Replacement: An Early Australian Case Series and Literature Review.

BACKGROUND: Transcatheter mitral valve implantation for degenerated bioprostheses has recently emerged as an alternative to redo mitral valve surgery, particularly in patients at high risk for reoperative cardiac surgery. We sought to examine our early experience of transcatheter transseptal mitral valve-in-valve procedures. METHODS: Prospectively collected data was retrospectively reviewed in patients undergoing transcatheter transseptal mitral valve-in-valve implantation using the Edwards Sapien 3 balloon expandable bioprosthesis (Edwards Lifesciences, Irvine, CA, USA). RESULTS: Seven (7) patients underwent the procedure between December 2017 and November 2018. Three (3) patients were young Indigenous Australians (age range 33-41years) who were not suitable for mechanical prostheses; four patients were elderly (age range 82-92 years) and considered high risk for reoperative surgery. The median (maximum, minimum) EuroSCORE II of the group was 7.32 (4.81, 19.89). Procedural success was obtained in six of the seven patients; these six patients had no significant complications and had a median hospital stay of 3 days. In one patient, the device displaced towards the left ventricle on inflation, resulting in left ventricular outflow tract obstruction and haemodynamic instability. Urgent redo mitral valve surgery and explantation of the transcatheter prosthesis was undertaken, however, this patient died postoperatively of multi-organ failure. Of the successfully deployed valves, the median (maximum, minimum) gradient across the new mitral prosthesis was 5.5 mmHg (4, 7) and only one patient had mild mitral regurgitation, all others had no or trivial regurgitation. At 30 days, these six patients are well and all are in New York Heart Association (NYHA) Class I. CONCLUSIONS: Our early experience with transcatheter transseptal mitral valve-in-valve implantation demonstrates this procedure to be feasible in our institution with acceptable early results. Further follow-up is necessary to determine the longevity of valves implanted in this manner, especially in the younger population.

Effect of Balloon Aortic Valvuloplasty on Mortality in Patients With Severe Aortic Stenosis Prior to Conservative Treatment and Surgical or Transcatheter Aortic Valve Replacement.

BACKGROUND: Outcomes following an initial strategy of balloon aortic valvuloplasty (BAV) prior to medical therapy or intervention with surgical or transcatheter aortic valve replacement (SAVR or TAVR) are unclear in the modern transcatheter intervention era. METHODS: A retrospective, observational cohort study of the echocardiography, cardiothoracic surgery and TAVR databases between 1 January 2006 and 31 December 2016 was performed to compare outcomes between all patients with severe aortic stenosis (AS) treated with or without BAV prior to medical or invasive therapy. RESULTS: 3,142 patients were available for analysis. 223 BAV treated patients had lower mortality relative to medically treated patients, particularly early (20.1% v. 7.6% at 6 months, 58.1% v. 52.5% at 5 years). Over 5 years, the adjusted hazard ratio (HR) was 0.62 (95% CI 0.48-0.80, p < 0.001). Compared with 630 patients proceeding directly to intervention, 75 patients receiving BAV experienced a higher mortality (HR = 2.76, 95% CI 2.07-3.66, p < 0.001). No subsequent excess perioperative mortality was observed with BAV compared with those receiving surgery directly (HR = 1.45, 95% CI 0.91-2.31, p = 0.117). CONCLUSIONS: The risk associated with BAV is low, and improves mortality compared with medical therapy. Balloon aortic valvuloplasty treated patients have poorer outcomes, but treatment with BAV does not increase perioperative mortality and may lessen it.

Ascending Aorta and Myocardial Mechanics in Patients with "Clinically Normal" Bicuspid Aortic Valve.

Aortic valve dysfunction and aortic wall changes are well-known complications of bicuspid aortic valve (BAV) disease. The aim of the present study was to investigate whether a remodeling process of the left ventricle (LV) is present in patients with isolated BAV. Twenty-two consecutive patients (39 ± 15 years, 9 males) with clinically normal BAV and 18 age- and gender-matched control subjects (37 ± 10 years, 9 males) were included. Cardiovascular magnetic resonance (CMR) imaging was performed to evaluate LV function, aortic valve morphology, aortic orifice area, and ascending aorta (AA) dimensions. Tissue-tracking analysis was applied to assess LV systolic and diastolic myocardial mechanics in the longitudinal, circumferential, and radial direction and AA circumferential strain (CS). No significant difference was observed between BAV and controls regarding LV ejection fraction and LV mass index. Tissue-tracking analysis demonstrated that BAV patients had significantly impaired LV systolic and diastolic myocardial mechanics. BAV patients had also significantly lower AA CS compared with controls. At multivariate analysis, the presence of BAV was the only variable significantly and independently related to the impaired AA and LV systolic myocardial mechanics. In conclusion, LV myocardial deformation properties are impaired among BAV patients. The impairment of LV systolic mechanics observed in BAV patients appears to be related only to the congenital abnormality of the aortic valve itself.

Instantaneous Decrease in Left Ventricular Afterload during Transcatheter Aortic Valve Implantation Results in Immediate Changes in Left Ventricular Strain.

Severe aortic stenosis causes chronic increased afterload on the left ventricle (LV) resulting in myocardial hypertrophy and ultimately dysfunction if left untreated. Transcatheter aortic valve implantation (TAVI) immediately decreases the afterload on the LV by reducing the pressure gradient through the aortic valve. In our study, we aim to evaluate immediate changes in LV mechanics using intra-procedural transesophageal echocardiography (TEE) to assess circumferential and radial strain via speckle tracking. Intra-operative TEE was performed during TAVI for 53 patients (mean age 84 ± 8 years). Two-dimensional images in the transgastric view were acquired at the level of the papillary muscle. Circumferential and radial strain was calculated using speckle tracking with Philips Qlab software. Global LV afterload was measured by calculating valvulo-arterial impedance (Zva). Immediately post-TAVI, there was a change in both radial strain rate (Pre: 0.73 ± 0.04 vs. Post: 0.88 ± 0.04 per second, P < 0.001) and circumferential strain rate (-0.53 ± 0.04 (pre) vs. -0.74 ± 0.04 (post) per second, P < 0.001). There was also an immediate improvement in circumferential global strain parameters (-14.5 ± 5% (pre) vs. -16.0 ± 4.7% (post), P < 0.05), whereas there was no significant change seen in global radial strain (15.6 ± 0.8% (pre) vs. 15.2 ± 0.9% (post), P = 0.69). No significant change was seen in LV ejection fraction (51.5 ± 14.2% (pre) vs. 52.1 ± 14.0% (post), P = 0.77). Speckle tracking using TEE images is feasible and identifies significant improvements in LV strain and strain rate immediately following TAVI that is not detected by conventional measure of LV function.

Coronary artery wall thickness of the left anterior descending artery using high resolution transthoracic echocardiography--normal range of values.

Recently it has been demonstrated that high resolution transthoracic echocardiography (HRTTE) is able to detect differences in the wall thickness of the left anterior descending coronary artery (LAD) between patients with coronary artery disease (CAD) and normal volunteers. We sought to validate this technique, develop a normal range of values and demonstrate the test-retest variability of each measurement. Two hundred forty-two volunteer participants had a HRTTE study to measure their LAD wall thickness, luminal, and external diameters. Thirty of these subjects had these measurements taken on 3 separate occasions by 2 different echosonographers. All subjects were free of clinical CAD, hypertension, hyperlipidemia, and diabetes mellitus. The average anterior wall thickness was 1.1 ± 0.2 mm; posterior wall thickness was 1.1 ± 0.2 mm, luminal diameter 2.2 ± 0.6 mm, and external elastic membrane (EEM) diameter 4.5 ± 0.9 mm. The bias of the measurements within the same operator for LAD wall thickness, luminal diameter, and EEM was 0.042, -0.06, and -0.077 mm, respectively. The bias of the measurements between 2 different operators for LAD wall thickness, luminal diameter, and EEM was 0.082, -0.077, and -0.027 mm, respectively. In conclusion, HRTTE measurement of the LAD vessel is reproducible within and between operators in normal volunteers. This technique therefore warrants further study as a potential screening modality for subclinical coronary atherosclerosis.

The evolving role of cardiac imaging in percutaneous valvular intervention.

Surgical therapies have represented the primary evidence-based intervention to alter the natural history of valvular heart disease (VHD), however, the increasing incidence of patients at high surgical risk due to age and related co-morbid conditions has given rise to the need for alternative strategies. Thus, percutaneous approaches to VHD therapy have emerged as an important therapeutic option. Cardiovascular imaging plays a critical role in patient screening for percutaneous valvular interventions, during the procedure itself, and as part of follow-up for the identification of implant success/failure and complications. The technical demands on imaging in this context are highly specific. Although imaging has a significant role in the broader evaluation of valvular heart disease mechanism and severity, the purpose of this paper is to summarise the particular goals of cardiovascular imaging in the work-up for, during, and in the follow-up of percutaneous valvular intervention.

Predictors of statin-induced regression of left anterior descending coronary artery wall thickness as measured by high-resolution transthoracic echocardiography.

BACKGROUND: Statin therapy has been shown to reduce cardiovascular risk after myocardial infarction (MI). Using a novel technique of high-resolution transthoracic echocardiography (HRTTE), we sought to assess the statin-induced changes in left anterior descending coronary artery (LAD) wall thickness in previously statin naive patients over a 12-month period. METHOD AND RESULTS: Thirty subjects underwent HRTTE assessment of their LAD wall thickness predischarge post-MI (non-LAD territory) and at 3, 6, and 12 months. The LAD anterior and posterior wall thickness and vessel luminal diameter were measured. Blood lipid levels were also assessed at each study visit. All subjects were started on moderate lipid-lowering therapy (40 mg of atorvastatin or simvastatin). There was a sustained decrease in total cholesterol (-23%), triglycerides (-19%), and low-density lipoprotein (-41%) at the 3-month visit from the baseline, with no change in high-density lipoprotein level. Overall, there was no change in the LAD wall thickness and external or vessel lumen diameter over the 12-month period. Of those that demonstrated regression, the only predictor of percentage change in the LAD wall thickness was the baseline LAD wall thickness. CONCLUSION: Despite a favorable change in blood lipid profile, no overall change in the LAD wall thickness was detected over a 12-month period in subjects on moderate statin therapy using HRTTE. However, using case-based analysis, regression was able to be predicted by the baseline LAD wall thickness. HRTTE may be an instructive noninvasive modality to assess response to statin intervention.

Nonvolumetric echocardiographic indices of right ventricular systolic function: validation with cardiovascular magnetic resonance and relationship with functional capacity.

PURPOSE: Right ventricular (RV) systolic function as measured by right ventricular ejection fraction (RVEF) has long been recognized as an important predictor of outcome in heart failure patients. The echocardiographic measurement of RV volumes and RVEF is challenging, however, owing to the unique geometry of the right ventricle. Several nonvolumetric echocardiographic indices of RV function have demonstrated prognostic value in heart failure. Comparison studies of these techniques with each other using RVEF as a benchmark are limited, however. Furthermore, the contribution of these various elements of RV function to patient functional status is uncertain. We therefore aimed to: (1) Determine which nonvolumetric echocardiographic index correlates best with RVEF as determined by cardiac magnetic resonance (CMR) imaging (the accepted gold standard measure of RV systolic function) and (2) Ascertain which echocardiographic index best predicts functional capacity. METHODS: Eighty-three subjects (66 with systolic heart failure and 17 healthy controls) underwent CMR, 2D echocardiography, and cardiopulmonary exercise testing for comparison of echocardiographic indices of RV function with CMR RVEF, 6-minute walk distance and VO(2 PEAK). RESULTS: Speckle tracking strain RV strain exhibited the closest association with CMR RV ejection fraction. Indices of RV function demonstrated weak correlation with 6-minute walk distance, but basal RV strain rate by tissue velocity imaging had good correlation with VO(2 PEAK). CONCLUSION: Strain by speckle tracking echocardiography and strain rate by tissue velocity imaging may offer complementary information in the evaluation of RV contractility and its functional effects.

Transcatheter mitral valve-in-valve: treatment of rheumatic heart disease in young patients.

BACKGROUND: Rheumatic heart disease (RHD) in young people presents a complex management problem. In Australia a significant proportion of those affected are Aboriginal and Torres Strait Islanders. Transcatheter mitral valve-in-valve (TMViV) replacement has emerged as an alternative to redo surgery in high-risk patients with degenerated mitral bioprostheses. The aim of this study is to review outcomes of TMViV replacement in young patients with RHD. METHODS: A single-centre, retrospective review of prospectively collected data on patients undergoing TMViV from December 2017 to June 2021. Primary outcome was major adverse cardiovascular events. Secondary outcome was post-operative trans-thoracic echocardiogram (TTE) results. RESULTS: There were seven patients with a mean age of 33 years and predominantly female (n = 5). Pre-operative comorbidities included diabetes (29%), chronic obstructive pulmonary disease (43%), left ventricular dysfunction (43%) and current smoking status (80%). Post-operative median length of hospital stay was 4 days with no post-operative renal failure, stroke, return to theatre, valve embolization or in hospital mortality. Post-operative TTE showed either nil or trivial central mitral regurgitation, no paravalvular leak and a median gradient of 5 mmHg (IQR 4.5, 7) across the new bioprosthesis; sustained at median follow-up of 22 months. CONCLUSION: Current literature of TMViV replacement is focused on an older population with concurrent comorbidities. This study provides a unique insight into TMViV replacement in a young cohort of patients with complex social and geographical factors which sometimes prohibits the use of a mechanical valve. The prevalence of RHD remains high for Aboriginal and Torres Strait Islanders, planning for future repeat valve operations should be considered from the outset. We consider TMViV as a part of a staged procedural journey for young patients with RHD.

Role of interatrial conduction in atrial fibrillation: Mechanistic insights from renewal theory-based fibrillatory dynamic analysis.

Background: Interatrial conduction has been postulated to play an important role in atrial fibrillation (AF). The pathways involved in interatrial conduction during AF remain incompletely defined. Objective: We recently showed physiological assessment of fibrillatory dynamics could be performed using renewal theory, which determines rates of phase singularity formation (λf) and destruction (λd). Using the renewal approach, we aimed to understand the role of the interatrial septum and other electrically coupled regions during AF. Method: RENEWAL-AF is a prospective multicenter observational study recruiting AF ablation patients (ACTRN 12619001172190). We studied unipolar electrograms obtained from 16 biatrial locations prior to ablation using a 16-electrode Advisor HD Grid catheter. Renewal rate constants λf and λd were calculated, and the relationships between these rate constants in regions of interatrial connectivity were examined. Results: Forty-one AF patients (28.5% female) were recruited. A positive linear correlation was observed between λf and λd (1) across the interatrial septum (λf r2 = 0.5, P < .001, λd r2 = 0.45, P < .001), (2) in regions connected by the Bachmann bundle (right atrial appendage-left atrial appendage λf r2 = 0.29, P = .001; λd r2 = 0.2, P = .008), and (3) across the inferior interatrial routes (cavotricuspid isthmus-left atrial septum λf r2 = 0.67, P < .001; λd r2 = 0.55, P < .001). Persistent AF status and left atrial volume were found to be important effect modifiers of the degree of interatrial renewal rate statistical correlation. Conclusion: Our findings support the role of interseptal statistically determined electrical disrelation in sustaining AF. Additionally, renewal theory identified preferential conduction through specific interatrial pathways during fibrillation. These findings may be of importance in identifying clinically significant targets for ablation in AF patients.

Tissue Doppler derived mechanical dyssynchrony does not change after cardiac resynchronization therapy.

BACKGROUND: Mechanical left ventricular (LV) dyssynchrony, as determined by tissue Doppler imaging (TDI), predicts response to cardiac resynchronization therapy (CRT). However, changes in TDI mechanical dyssynchrony after CRT implantation have only limited investigation. Our objective was to detect changes in the extent and location of TDI mechanical dyssynchrony pre- and post-CRT, and to explore their relationship in response to CRT. METHODS: Thirty-nine consecutive patients undergoing CRT implantation for chronic heart failure underwent TDI analysis pre-CRT and up to 12 months post-CRT. Regional dyssynchrony was determined by the time to systolic peak velocity of opposing LV walls. Dyssynchrony was defined as a difference in time to peak contraction of >105 msec. Two patients were excluded, as suitable coronary venous access was not available. RESULTS: Of the 37 patients, 28 (76%) had significant mechanical dyssynchrony pre-CRT. Of those with dyssynchrony, 18 (64%) had septal delay and 10 (36%) had LV free wall delay. Post-CRT, 29 (78%) patients had significant mechanical dyssynchrony, 17 (59%) with septal delay, and 12 (41%) with LV free wall delay. There was no difference in both the amount of dyssynchrony (P=0.8) or the location of the dyssynchrony (P=0.5), before and after CRT, even though 28 (76%) were considered responders based on symptomatic and echocardiographic parameters. CONCLUSION: The TDI-derived dyssynchrony does not change with CRT despite significant symptomatic and echocardiographic improvement in cardiac function. The TDI is of limited utility for monitoring response to CRT.

Impact of increased augmentation index and valvuloarterial impedance on symptom recovery after aortic valve replacement for severe aortic stenosis.

BACKGROUND: Aortic stenosis (AS) is a common valvular disorder with a large symptomatic burden resulting from increased myocardial workload due to valvular obstruction. The contribution of increased afterload from arterial stiffness on symptoms is uncertain. The purpose of this analysis was to determine the symptomatic impact of arterial stiffness as determined by Applanation Tonometry. METHODS: Eighty-eight patients with severe AS undergoing intervention with transcatheter aortic valve replacement (TAVR) (n = 65) or surgical aortic valve replacement (SAVR) (n = 23) were prospectively enrolled. Symptoms were recorded using the NYHA Class, Kansas City Cardiomyopathy Questionnaire (KCCQ) and a 6 min walk test (6MWT) at baseline, and 1- and 6-months post intervention. Pulse Wave Analysis (PWA) using Applanation Tonometry was performed at all reviews, including the augmentation index (AIx). RESULTS: Patients undergoing TAVR were older, with worse renal function and lower aortic valve areas, but were otherwise similar. There was no significant difference between the augmentation index of our AS population compared with an age matched reference population (p = 0.89).Symptoms significantly improved after intervention according to NYHA Class, KCCQ and 6MWT. Additionally, with adjustment, the initial augmentation index correlated with the final KCCQ (Coeff. = -0.383, p = 0.02) and NYHA Class (Coeff. = 0.012, p = 0.03) and a baseline AIx value in the top quartile resulted in a significantly worse final KCCQ (95.1 v 85.2, p = 0.048) relative to the bottom 3 quartiles. CONCLUSIONS: According to our analysis, an elevated baseline AIx is associated with a poorer symptomatic recovery after aortic valve intervention and so is worthy of consideration when assessing potential symptomatic benefit.

Advanced Echocardiographic Imaging for Prediction of SCD in Moderate and Severe LV Systolic Function.

OBJECTIVES: This study sought to determine the long-term prognostic value of myocardial deformation imaging by echocardiography in risk stratification of sudden cardiac death (SCD) and malignant ventricular arrhythmias (VAs) in a large consecutive cohort of patients with left ventricular (LV) systolic impairment, irrespective of its etiology. BACKGROUND: Left ventricular ejection fraction (LVEF) is limited for prediction of SCD. Echocardiographic strain-derived mechanical dispersion (MD) and global longitudinal strain (GLS) has been linked to VA and SCD. However, due to low event rates, the role of these parameters has not been fully elucidated. METHODS: Consecutive clinically stable patients who underwent echocardiographic study performed in an outpatient setting from 2008 to 2014 with a Simpson left ventricular ejection fraction (LVEF) ≤45% were included in the study. Strain analysis was performed in which the LV was separated into 16 segments for regional analysis. Mechanical dispersion (MD) was calculated as the SD of the time to peak of each of the 16 regions. Outcome data were obtained from medical records. RESULTS: A total of 939 patients were included in the study, with median LVEF of 37% (interquartile range 30% to 42%). At follow-up (91.4 ± 23.4 months), 96 VA events had occurred. Multivariate analysis demonstrated that only MD ≥75 ms (hazard ratio: 9.45; 95% confidence interval: 4.75 to 18.81; p < 0.0001) was predictive of VA events. Low MD predicted a low event rate, irrespective of LVEF. CONCLUSIONS: Using LVEF alone is inferior for prediction of VA and SCD, particularly in patients with moderately reduced LVEF. MD is easily obtained from standard echocardiographic images and can be used to improve risk prognosis, particularly in patients who are currently excluded from cardiac defibrillator insertion based on LVEF.

Prospective cross-sectional study using Poisson renewal theory to study phase singularity formation and destruction rates in atrial fibrillation (RENEWAL-AF): Study design.

BACKGROUND: Unstable functional reentrant circuits known as rotors have been consistently observed in atrial fibrillation and are mechanistically believed critical to the maintenance of the arrhythmia. Recently, using a Poisson renewal theory-based quantitative framework, we have demonstrated that rotor formation (λf) and destruction rates (λd) can be measured using in vivo electrophysiologic data. However, the association of λf and λd with clinical, electrical, and structural markers of atrial fibrillation phenotype is unknown. METHODS: RENEWAL-AF is a multicenter prospective cross-sectional study recruiting adult patients with paroxysmal or persistent atrial fibrillation undergoing clinically indicated catheter ablation. Patients will undergo intraprocedural electrophysiologic atrial fibrillation mapping, with λf and λd to be determined from 2-minute unipolar electrogram recordings acquired before ablation. The primary objective will be to determine the association of λf and λd as markers of fibrillatory dynamics with clinical, electrical, and structural markers of atrial fibrillation clinical phenotype, measured by preablation transthoracic echocardiogram and cardiac magnetic resonance imaging. An exploratory objective is the noninvasive assessment of λf and λd using surface ECG characteristics via a machine learning approach. RESULTS: Not applicable. CONCLUSION: This pilot study will provide insight into the correlation between λf/λd with clinical, electrophysiological, and structural markers of atrial fibrillation phenotype and provide a foundation for the development of noninvasive assessment of λf/λd using surface ECG characteristics will help expand the use of λf/λd in clinical practice.

The Spectrum of Change in the Elite Athlete's Heart.

BACKGROUND: Extreme levels of both strength and aerobic training result in increased left ventricular (LV) and right ventricular (RV) volumes and LV mass, a key component of athletes' heart. The aim of this study was to document temporal changes in the hearts of elite professional athletes (Australian Football League players) over a 2- to 6-year period. METHODS: Thirty-six Australian Football League players with 3.5 ± 2.7 years of professional training at enrollment prospectively underwent echocardiography in the preseasons of 2009, 2013, and 2015. At each time point, LV dimension and contractility and RV dimension, area, and contractility were measured using two-dimensional echocardiography. LV volumes, ejection fraction, and mass were measured using three-dimensional echocardiography. RESULTS: The mean age at baseline was 21.8 ± 2.6 years (range, 18-29 years). Most players (n = 20) had increases in fitness between studies (mean maximal oxygen uptake, 62.3 ± 3.6 vs 64.3 ± 2.1 mL/kg/min). In these players, there were increases in both LV and RV size and in LV mass. Players who were >25 years of age at their baseline scans demonstrated a trend toward increases in RV size and a decline in RV global longitudinal strain. Fitness level and playing position also affected the degree of physiological athletic cardiac remodeling. CONCLUSIONS: Australian football is a sport that involves both strength and aerobic training. This study, unique in its length and detail, demonstrates that remodeling in the athlete's heart is a continuous spectrum of change. This remodeling occurs over time in response to high levels of exercise, with proportional increase in LV mass and LV dimensions.

Multidisciplinary transcatheter aortic valve replacement heart team programme improves mortality in aortic stenosis.

Objectives: To analyse the effect of the implementation of a transcatheter aortic valve replacement (TAVR) and multidisciplinary heart team programme on mortality in severe aortic stenosis (AS). Methods: A retrospective, observational cohort study was performed using the echocardiography, cardiothoracic surgery and TAVR databases between 1 January 2006 and 31 December 2016. Outcomes were compared between the pre- and post-TAVR programme eras in a tertiary referral centre providing transcatheter and surgical interventions for AS.All-cause mortality within 5 years from diagnosis was determined for 3399 patients with echocardiographically defined severe AS. Results: Of 3399 patients, there were 210 deaths (6.2%) at 30 days and 1614 deaths (47.5%) at 5 years.Overall, patients diagnosed in the post-TAVR programme era were older, with a lower ejection fraction and more severe AS, but were less comorbid.Among 705 patients undergoing intervention, those in the post-TAVR programme era were older, with a lower ejection fraction and more severe AS but no significant differences in comorbidities.Using an inverse probability weighted cohort and a Cox proportional hazards model, a significant mortality benefit was noted between eras alone (HR=0.86, 95% CI 0.77 to 0.97, p=0.015). When matching for age, comorbidities and valve severity, this benefit was more evident (HR=0.82, 95% CI 0.73 to 0.92, p=0.001).After adjusting for the presence of aortic valve intervention, a significant benefit persisted (HR=0.84, 95% CI 0.75 to 0.95, p=0.005). Conclusion: The implementation of a TAVR programme is associated with a mortality benefit in the population with severe AS, independent of the expansion of access to intervention.

Changes in left anterior descending coronary artery wall thickness detected by high resolution transthoracic echocardiography.

Recently, it has been demonstrated that high-resolution transthoracic echocardiography (HRTTE) is able to detect differences in the wall thickness of the left anterior descending coronary artery (LAD) between patients with coronary artery disease (CAD) and normal volunteers. The aim of this study was to further validate this technique. One hundred ten volunteers, 58 patients with angiographically proved CAD and 52 control subjects, underwent assessments of their LADs using HRTTE. Anterior and posterior wall thicknesses differed between subjects in the CAD group and controls (1.9 +/- 0.6 vs 1.2 +/- 0.3 mm, p <0.001, and 1.8 +/- 0.5 vs 1.2 +/- 0.3 mm, p <0.001, respectively). External LAD diameter was also greater in subjects in the CAD group compared with controls (5.2 +/- 1.9 vs 4.4 +/- 0.9 mm, respectively, p = 0.01). However, there was no difference in luminal diameter between subjects in the CAD group and the controls (1.9 +/- 0.9 vs 2.1 +/- 0.8 mm, respectively, p = 0.3). In conclusion, HRTTE demonstrated that LAD wall thicknesses and external diameters in patients with CAD were significantly larger than in normal volunteers. Luminal diameter, however, was maintained in the 2 groups, indicating that subjects in the CAD group had undergone positive remodeling at the site measured. This objectively visualized evidence of coronary atherosclerosis with HRTTE would likely be undetected during coronary angiography.