Patient evaluation and selection for transcatheter aortic valve replacement: the heart team approach

Predicting pressure gradient using artificial intelligence for transcatheter aortic valve replacement

Objective

After transcatheter aortic valve replacement, the mean transvalvular pressure gradient indicates the effectiveness of the therapy. The objective is to develop artificial intelligence to predict the post-transcatheter aortic valve replacement aortic valve pressure gradient and aortic valve area from preprocedural echocardiography and computed tomography data.

Methods

A retrospective study was conducted on patients who underwent transcatheter aortic valve replacement due to aortic valve stenosis. A total of 1091 patients were analyzed for pressure gradient predictions (mean age 76.8 ± 9.2 years, 57.8% male), and 1063 patients were analyzed for aortic valve area predictions (mean age 76.7 ± 9.3 years, 57.2% male). An artificial intelligence learning model was trained (training: n = 663 patients, validation: n = 206 patients) and tested (testing: n = 222 patients) to predict pressure gradient, and a separate artificial intelligence learning model was trained (training: n = 640 patients, validation: n = 218 patients) and tested (testing: n = 205 patients) for predicting aortic valve area.

Results

The mean absolute error for pressure gradient and aortic valve area predictions was 3.0 mm Hg and 0.45 cm2, respectively. Valve sheath size, body surface area, and age were determined to be the top 3 predictors for pressure gradient, and valve sheath size, left ventricular ejection fraction, and aortic annulus mean diameter were identified to be the top 3 predictors of post-transcatheter aortic valve replacement aortic valve area. A training dataset size of more than 500 patients demonstrated good robustness of the artificial intelligence models for pressure gradient and aortic valve area.

Conclusions

The artificial intelligence-based algorithm has demonstrated potential in predicting post-transcatheter aortic valve replacement transvalvular pressure gradient predictions for patients with aortic valve stenosis. Further studies are necessary to differentiate pressure gradient between valve types.

Frailty Phenotype and Deficit Accumulation Frailty Index in Predicting Recovery After Transcatheter and Surgical Aortic Valve Replacement

BACKGROUND

Frailty phenotype and deficit-accumulation frailty index (FI) are widely used measures of frailty. Their performance in predicting recovery after surgical aortic valve replacement (SAVR) and transcatheter aortic valve replacement (TAVR) has not been compared.

METHODS

Patients undergoing SAVR (n = 91) or TAVR (n = 137) at an academic medical center were prospectively assessed for frailty phenotype and FI. Outcomes were death or poor recovery, defined as a decline in ability to perform 22 daily activities and New York Heart Association class 3 or 4 at 6 months after surgery. The predictive ability of frailty phenotype versus FI and their additive value to a traditional surgical risk model were evaluated using C-statistics, net reclassification improvement (NRI), and integrated discrimination improvement.

RESULTS

TAVR patients had higher prevalence of phenotypic frailty (85% vs 38%, p < .001) and greater mean FI (0.37 vs 0.24, p < .001) than SAVR patients. In the overall cohort, FI had a higher C-statistic than frailty phenotype (0.74 vs 0.63, p = .01) for predicting death or poor recovery. Adding FI to the traditional model improved prediction (NRI, 26.4%, p = .02; integrated discrimination improvement, 7.7%, p < .001), while adding phenotypic frailty did not (NRI, 4.0%, p = .70; integrated discrimination improvement, 1.6%, p = .08). The additive value of FI was evident in TAVR patients (NRI, 42.8%, p < .01) but not in SAVR patients (NRI, 25.0%, p = .29). Phenotypic frailty did not add significantly in either TAVR (NRI, 6.8%, p = .26) or SAVR patients (NRI, 25.0%, p = .29).

CONCLUSIONS

Deficit-accumulation FI provides better prediction of death or poor recovery than frailty phenotype in older patients undergoing SAVR and TAVR.

Multidisciplinary decision-making in mitral valve disease: the mitral valve heart team

Background

Although decision-making using the heart-team approach is apparently intuitive and has a class I recommendation in most recent guidelines, supportive data is still lacking. The current study aims to demonstrate the individualised clinical pathway for mitral valve disease patients and to evaluate the outcome of all patients referred to the dedicated mitral valve heart team.

Methods

All patients who were evaluated for mitral valve pathology with or without concomitant cardiac disease between 1 January 2016 and 31 December 2016 were prospectively followed and included. Patients were evaluated, and a treatment strategy was determined by the dedicated mitral valve heart team.

Results

One hundred and fifty-eight patients were included; 67 patients were treated surgically (isolated and concomitant surgery), 20 by transcatheter interventions and 71 conservatively. Surgically treated patients had a higher 30-day mortality rate (4.4%), which decreased when specified to a dedicated surgeon (1.7%) and in primary, elective cases (0%). This was also observed for major adverse events within 30 days. Residual mitral regurgitation >grade 2 was more frequent in the catheter-based intervention group (23.5%) compared to the surgical group (4.8%).

Conclusion

In conclusion, the implementation of a multidisciplinary heart team for mitral valve disease is a valuable approach for the selection of patients for different treatment modalities. Our research group will focus on a future comparative study using historical cohorts to prove the potential superiority of the dedicated multidisciplinary heart-team approach.

Two-Year Outcomes of Transcatheter Compared With Surgical Aortic Valve Replacement in "Minimal-Risk" Patients Lacking EuroSCORE Co-morbidities (from the TAVIK Registry)

We aimed to compare the outcomes of transcatheter aortic valve implantation (TAVI) with surgical aortic valve replacement (SAVR) in an elderly but nonfrail, minimally co-morbid population. Although data comparing these 2 procedures in intermediate- and low-risk patients are mounting, no distinction has been made between co-morbidity and age/gender as driving forces for surgical risk. Patients undergoing isolated TAVI or SAVR between May 2008 and March 2015 were documented. Data for 225 patients (TAVI 132, SAVR 93) aged ≥75 and <86 years and fulfilling minimal-risk criteria were analyzed. Patients who underwent TAVI were older (80.7 vs 77.4 years, p <0.0001) and had a higher mean Society of Thoracic Surgeons score (2.16% vs 1.72%, p <0.0001). Mild prosthetic valve regurgitation (odds ratio [OR] 4.9, 95% confidence interval [CI] 3.34 to 7.20) was more likely after TAVI, as were renal complications (predominantly stage I acute kidney injury; OR 2.86, 95% CI 1.79 to 4.55) and new pacemaker implantation (OR 3.33, 95% CI 1.76 to 6.26) at 30 days; however, life-threatening bleeding (OR 0.58, 95% CI 0.36 to 0.93) and reintervention for bleeding (OR 0.03, 95% CI 0.01 to 0.13) were less likely. Survival was comparable between groups at 30 days (99.2% vs 100%, p = 1.0) and 1 year (96.2% vs 96.8%, OR 0.85, 95% CI 0.20 to 3.63, p = 0.823), but it was poorer for patients who underwent TAVI at 2 years (OR 0.31, 95% CI 0.16 to 0.61). In conclusion, the short-term outcomes of TAVI in elderly, low-risk, minimally co-morbid patients appear to be similar to those of SAVR, with access-specific complications. Although these results point toward the potential for more liberal use of TAVI in minimal-risk patients, poorer midterm survival remains a concern, requiring further exploration.

Palliative care in end-stage valvular heart disease

Valvular heart disease (VHD), particularly aortic valve disease, is prevalent with increasing incidence. When surgery is not possible, or when risks outweigh benefits, percutaneous treatment options may offer effective alternatives. However, procedures may not always go as planned, and frail patients or those whose symptoms are caused by other comorbidities may not benefit from valve intervention at all. Significant effort should be made to assess frailty, comorbidities and patient goals prior to intervention. Palliative care (PC) should play a critical role in the care of patients with severe valve disease. PC is specialised medical care that aims to optimise health-related quality of life by managing symptoms and clarifying patient values and goals of care. It should be implemented at the time of diagnosis and continue throughout the disease course. Because of the paucity of studies dedicated to the provision of PC to patients with advanced VHD, further research is needed.

Is TAVR Ready for the Global Aging Population?

The emergence of the global pandemic of chronic diseases necessitates critical assessment of interventions that can be targeted at both the individual and population levels. Among cardiovascular diseases, the increasing prevalence of valvular heart diseases such as aortic stenosis parallels the rising burden of atherosclerotic cardiovascular diseases. As an alternative to surgical aortic valve replacement, technological innovation has allowed development of minimally invasive transcatheter aortic valve replacement (TAVR). This review examines whether TAVR can be applicable in low-resource regions across the world. Although revolutionary, TAVR is currently complex and requires a "Heart Team" approach for optimized patient care. We propose the emergence of telemedicine networks, newer valve designs that allow implementation of minimal approaches, and the use of minimal numbers of specialists for adapting TAVR to settings where surgical backup is not available. With efforts to reduce resource utilization, these alternate strategies have the potential to affect implementation of TAVR globally.

The impact of frailty on mortality after transcatheter aortic valve replacement

Frailty is a notably common problem in patients with severe aortic stenosis (AS) undergoing transcatheter aortic valve replacement (TAVR) evaluation. Studies have demonstrated significant associations between frailty and worse outcomes in patients undergoing TAVR including higher risks of disability and mortality and admissions to long-term care facility. While there are multiple methods to identify and measure frailty, there is a critical need for a precise definition of frailty and its standardized assessment protocol based on well-established tests covering all aspects of the frailty, as a syndrome. Incorporation of the available frailty evaluation into pre-operative risk assessments chances of morbidity or mortality following surgery can help enhancing performance and improve shared decision-making between physicians and their patients. In this review, we present the perspectives of the impact of frailty on mortality in patients undergoing TAVR.

Transcatheter aortic valve implantation in the elderly: who to refer?

In recent years, experience with transcatheter aortic valve implantation has led to improved outcomes in elderly patients with severe aortic stenosis (AS) who may not have previously been considered for intervention. These patients are often frail with significant comorbid conditions. As the prevalence of AS increases, there is a need for improved assessment parameters to determine the patients most likely to benefit from this novel procedure. This review discusses the diagnostic criteria for severe AS and the trials available to aid in the decision to refer for aortic valve procedures in the elderly.