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.

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.

Microwave assisted green synthesis of silver nanoparticles for optical, catalytic, biological and electrochemical applications.

Plant-derived nanoparticles have multi-functionalities owing to their ecological origin and biocompatible nature. A novel and stable silver nanoparticle (AgNP) was reported here using Cyanthillium cinereum (C. cinereum) as a reducing as well as capping agent by rapid microwave-assisted green method. The synthesized nanoparticles revealed their crystalline and spherical nature with an average size of 19.25 ± 0.44 nm in HR-TEM analysis. The excitation of electrons from occupied d-bands to states above the Fermi level while employing photoluminescence studies of AgNP indicated their awesome optical properties. Rapid decomposition of dangerous organic dyes like methylene blue and fuchsine in the catalytic presence of AgNP was evidenced from simple UV-visible spectral analysis. In vitro antioxidant potential assessed by DPPH assay indicated an IC50 value of 40.80 ± 0.14 µg/mL for the new AgNP. A substantial control on the growth of pathogenic bacteria such as Staphylococcus aureus and Klebsiella pneumonia can be achieved by synthesized nanoparticles as demonstrated by the well diffusion method. AgNP was also functioned as a non-enzymatic electrochemical sensor with a sharp oxidation peak with peak potentials at 0.366 V and it has a wide application as a bio sensor in neurobiology especially in the detection of neurotransmitters like dopamine with high sensitivity.

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.

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.

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.

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.

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.

New Test, Old Disease: A Case Series of Diabetic Ketoalkalosis.

BACKGROUND: Diabetic ketoalkalosis (DKAlk) was first described in 1967 as a rare complication of diabetic ketoacidosis with normal or elevated pH/bicarbonate and elevated anion gap (AG) from high ß-hydroxybutyrate (BHB). OBJECTIVE: We report a case series of patients with DKAlk to show how venous blood gas (VBG) electrolytes alone may misdiagnose these patients. METHODS: This was a case series of DKAlk patients with concomitant VBG and basic metabolic panel (BMP) electrolytes who met the following criteria for DKAlk: BMP hyperglycemia (glucose >250 mg/dL), elevated AG (>15 mEq/L), elevated BHB (>1.2 mmol/L), and high Delta (Δ) gap (>6 mEq/L [bicarbonate gap (BG): measured bicarbonate - 24] - [AG - 12]). Data are reported as median with interquartile range (IQR) (25%, 75%) and group comparisons utilized Mann-Whitney U test (two-tailed, α = 0.05). RESULTS: We found 10 patients with DKAlk in 2 months. Patients ranged in age from 13 to 77 years, 50% were male, and all were African American. Most patients (8 of 10) were vomiting with hyperglycemia (350 to >600 mg/dL). DKAlk BMP AG ranged from 18 to 34 mmol/L and BHB from 1.74 to 9.09 mmol/L. For bicarbonate, we found no significant difference between VBG (24 mmol/L) and BMP (22 mmol/L) (p = 0.796). VBG chloride (98 mmol/L) was significantly higher than BMP chloride (88 mmol/L) (p < 0.005). This falsely elevated VBG chloride resulted in undervaluing of all VBG AGs, missing almost all of the patients with DKAlk. CONCLUSIONS: We found that DKAlk is more common than previously reported. We recommend screening with BMP electrolytes and BHB levels for hyperglycemic ED patients who are vomiting or suspected of hypovolemia.

Poor Long-Term Survival in Patients With Moderate Aortic Stenosis.

BACKGROUND: Historical data suggesting poor survival in patients with aortic stenosis (AS) who do not undergo treatment are largely confined to patients with severe AS. OBJECTIVES: This study sought to determine the prognostic impact of all levels of native valvular AS. METHODS: Severity of AS was characterized by convention and by statistical distribution in 122,809 male patients (mean age 61 ± 17 years) and 118,494 female patients (mean age 62 ± 19 years), with measured aortic valve (AV) mean gradient, peak velocity, and/or area. The relationship between AS severity and survival was then examined during median 1,208 days (interquartile range: 598 to 2,177 days) of follow-up. Patients with previous aortic valve intervention were excluded. RESULTS: Overall, 16,129 (6.7%), 3,315 (1.4%), and 6,383 (2.6%) patients had mild, moderate, and severe AS, respectively. On an adjusted basis (vs. no AS; 5-year mortality 19%), patients with mild to severe AS had an increasing risk of long-term mortality (adjusted hazard ratio: 1.44 to 2.09; p < 0.001 for all comparisons). The 5-year mortality was 56% and 67%, respectively, in those with moderate AS (mean gradient 20.0 to 39.0 mm Hg/peak velocity 3.0 to 3.9 m/s) and severe AS (≥40.0 mm Hg, ≥4.0 m/s, or AV area <1.0 cm2 in low-flow, low-gradient severe AS). A markedly increased risk of death from all causes (5-year mortality >50%) and cardiovascular disease was evident from a mean AV gradient >20.0 mm Hg (moderate AS) after adjusting for age, sex, left ventricular systolic or diastolic dysfunction, and aortic regurgitation. CONCLUSIONS: These data confirm that when left untreated, severe AS is associated with poor long-term survival. Moreover, they also suggest poor survival rates in patients with moderate AS. (National Echocardiographic Database of Australia [NEDA]; ACTRN12617001387314).

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.

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.

Threshold of Pulmonary Hypertension Associated With Increased Mortality.

BACKGROUND: There is increasing evidence that current thresholds for diagnosing pulmonary hypertension (PHT) underestimate the prognostic impact of PHT. OBJECTIVES: The aim of this study was to determine the prognostic impact of increasing pulmonary pressures within the National Echocardiography Database of Australia cohort (n = 313,492). METHODS: The distribution of estimated right ventricular systolic pressure (eRVSP) was examined in 157,842 men and women. All had data linkage to long-term survival during median follow-up of 4.2 years (interquartile range: 2.2 to 7.5 years). RESULTS: The cohort comprised 74,405 men and 83,437 women 65.6 ± 17.7 years of age. Overall, 17,955 (11.4%), 7,016 (4.4%), and 4,515 (2.9%) subjects had eRVSP levels indicative of mild (40 to 49 mm Hg), moderate (50 to 59 mm Hg), or severe (≥60 mm Hg) PHT, respectively, assuming a right atrial pressure of 5 mm Hg. These subjects were more likely to die during long-term follow up (for severe PHT, adjusted hazard ratio: 9.73; 95% confidence interval: 8.60 to 11.0; p < 0.001). After adjustment for age, sex, and evidence of left heart disease, those subjects with eRVSP levels within the third (28.05 to 32.0 mm Hg; hazard ratio: 1.410; 95% confidence interval: 1.310 to 1.517) and fourth (32.05 to 38.83 mm Hg; hazard ratio: 1.979; 95% confidence interval: 1.853 to 2.114) quintiles had significantly higher mortality (p < 0.001) than those in the lowest quintile. Accordingly, a clear and consistent threshold of increased mortality (including 1- and 5-year actuarial mortality) around an eRVSP of 30.0 mm Hg was evident. CONCLUSIONS: In this large and unique cohort, the prognostic impact of clinically accepted levels of PHT was confirmed. Moreover, a distinctly lower threshold for increased risk for mortality (eRVSP >30.0 mm Hg) indicative of PHT was identified. (A Longitudinal Cohort Study of Echocardiograms From Public and Private Echocardiography Laboratories From Around Australia, Linked With the National Deaths Index; ACTRN12617001387314).

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.