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Nkomo, Vuyisile T

0000-0001-6095-5579

Mayo Clinic

Mayo Clinic

Citations 31

Decoding the complexity of tricuspid regurgitation prognostic drivers using explainable artificial intelligence

European Heart Journal - Cardiovascular Imaging | June 27, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1093/ehjci/jeag168 | PMID 42363702

Abstract Aims Prognosis in tricuspid regurgitation (TR) is shaped by complex clinical and haemodynamic interactions, complicating risk stratification. We aimed to use explainable artificial intelligence (EAI) to model these relationships and identify key predictors of outcomes. Methods and results We analysed long-term all-cause mortality in a large prospective registry of patients with native TR across the full severity spectrum. Patients underwent detailed clinical evaluation and quantitative Doppler-echocardiography. Supervised EAI models were applied to identify and rank predictors of mortality under medical therapy, capturing non-linear associations and interactions among baseline characteristics. Among 9761 patients [mean age 73 ± 15 years; 56.9% women; effective regurgitant orifice area (EROA) 40 (30–56) mm2; regurgitant volume 39 (29–53) mL/beat; 42% severe TR], 2676 deaths occurred during 3.8 ± 4.6 years of follow-up. EAI identified and ranked 20 prognostic determinants of survival. Haemodynamic measures, led by elevated pulmonary-artery systolic and right-atrial pressures, were strongest, followed by age and comorbidity. TR-related variables ranked next, led by right ventricular dysfunction and EROA, which outperformed integrative TR grade and TRIScore. Left-ventricular parameters were less influential. Non-linear effects, including those involving ejection fraction, and interactions such as higher EROA-related risk with elevated pulmonary pressures or lower TRIScore (both P < 0.03) were observed. Proportional hazards models confirmed EROA as the strongest TR severity marker (P < 0.0001), with excess mortality beginning at 40 mm2 and increasing further at 60 mm2. Conclusion EAI ranked mortality predictors in TR, highlighting patient factors, haemodynamics, TR-specific measures, and left-ventricular function. Among TR-specific measures, EROA and TRIScore were most prognostic. Recognizing their impact can refine risk stratification, guide intervention timing, and inform long-term management.
Structural heart disease screening using artificial intelligence–enabled electrocardiogram and novice handheld cardiac ultrasound: a cost analysis

European Heart Journal Open | March 18, 2026 | Volume: 6 | Issue: 2 | Pages: No page available

10.1093/ehjopen/oeag049 | PMID 41970469

Abstract Aims Early detection of structural heart disease (SHD) improves patient outcomes. However, population-based screening is not recommended due to the lack of accurate and cost-effective tools. We evaluated the costs of artificial intelligence–enabled electrocardiogram (AI-ECG) alone vs. AI-ECG followed by handheld cardiac ultrasound (HCU) for SHD screening. Methods and results We performed a model-based cost analysis using data from 286 adult patients who underwent ECG and same-day HCU performed by a novice operator. Transthoracic echocardiogram (TTE) was the reference standard. We compared two screening strategies: (i) AI-ECG alone and (ii) a stepwise approach (AI-ECG followed by HCU). We assessed costs per diagnosis of aortic stenosis (AS), increased left ventricular wall thickness (ILVWT), and left ventricular systolic dysfunction (LVSD). Sensitivity analyses were conducted for varying disease prevalence. The stepwise approach decreased the cost per diagnosis of AS from $6386 (AI-ECG alone) to $2746 (57.0% savings), ILVWT from $4448 to $2895 (34.9% savings), and LVSD from $1469 to $1296 (11.8% savings). Overall, the cost per diagnosis for all SHDs combined decreased from $1940 to $1570 (19.1% savings). Sensitivity analysis demonstrated that cost savings were inversely proportional to disease prevalence. Nevertheless, stepwise screening remained cost-saving compared with AI-ECG alone until prevalence exceeded ∼55.9% for AS, 28.9% for ILVWT, 20.7% for LVSD, and 40.8% for all SHDs combined. Conclusion A stepwise screening strategy incorporating HCU after a positive AI-ECG reduces the immediate costs of SHD detection by minimizing unnecessary TTEs. This approach may enhance the feasibility of population-based SHD screening, particularly in lower-prevalence settings.
Survival and Risk Profile of Patients With Significant Tricuspid Regurgitation by Etiology

Journal of the American Heart Association | February 27, 2026 | Volume: 15 | Issue: 5 | Pages: No page available

10.1161/jaha.125.044323 | PMID 41757445

Background Tricuspid regurgitation (TR) is a common valvular disorder that can affect patients’ quality of life and survival. The impact of TR etiology on overall survival and the associated risk factors in each subgroup are not well studied. Methods Multisite, retrospective study evaluating survival based on TR etiology using Kaplan–Meier and Cox regression models. Stepwise approach was used to define TR etiology (≥moderate): primary (PTR; presence of a primary valvular pathology), lead associated (LTR; lead interfering with closure), and secondary TR (STR) in the setting of left‐sided valvular disease, left ventricular disease, other causes of pulmonary hypertension, right ventricular disease, and atrial secondary TR. Results A total of 12 899 patients were included (3% PTR, 90% STR, 7% LTR). The mean age was 68±14, 73±13, and 71±13 years, respectively (44%–55% female patients). Adjusting for age, sex, and TR severity, patients with PTR had better overall survival (PTR: reference; STR hazard ratio [HR], 1.4 [1.2–1.6], LTR HR, 1.5 [1.1–1.7]). On multivariable Cox regression, the Tricuspid Regurgitation Impact on Outcomes score was associated with mortality across all groups ( P <0.05 for all). In addition, other risk factors associated with worse outcomes included pulmonary hypertension and ≥moderate right ventricular enlargement in PTR; left‐sided valvular disease, pulmonary hypertension, and ≥moderate right ventricular dysfunction in STR; and left ventricular disease and ≥moderate right ventricular dysfunction in LTR. Conclusions Patients with PTR have better survival than STR and LTR. Tricuspid Regurgitation Impact on Outcomes score was associated with mortality across etiologies, whereas other risk factors are etiology specific. Improved risk profiling may enhance patient selection, treatment decisions, and outcomes.
Impact of contemporary guideline-directed medical therapy on secondary mitral and tricuspid regurgitation in heart failure with reduced ejection fraction

European Journal of Heart Failure | February 17, 2026 | Volume: No volume available | Issue: No issue available | Pages: No page available

10.1093/ejhf/xuag047 | PMID 41771144

Abstract Aims We aimed to assess regression and development rates of ≥moderate secondary mitral regurgitation (MR) and tricuspid regurgitation (TR) in patients with heart failure and reduced ejection fraction (HFrEF) receiving contemporary guideline-directed medical therapy (GDMT). Methods Patients with a &lt;1 year diagnosis of HFrEF with mildly (40% ≤ EF &lt; 50%) or moderately (&lt;40%) reduced EF enrolled in GDMT titration programme 2019–2024 were identified. Regression rates of ≥moderate MR/TR to ≤mild and development rates of incident ≥moderate MR/TR were calculated. Results Among 844 patients [median age 64; 68% men; 26% mildly reduced EF; 24% New York Heart Association (NYHA) Class III/IV], 28% had ≥moderate MR and 14% had ≥moderate TR. Over median 7.1 months, 171 (75%) patients with ≥moderate MR and 87 (75%) of patients with ≥moderate TR experienced regression to no/mild MR and TR, respectively. Conversely, over median 13 months, incident ≥moderate MR and TR developed in 5% and 6%, respectively, of patients with no/mild baseline MR and TR. Number of GDMT medications at follow-up was less in patients who did not have MR/TR regression (vs who did) and in patients who developed MR/TR (vs who did not). Patients with NYHA Class I/II received a similar number of GDMT and had a similar rate of MR and TR regression and development vs patients with NYHA Class III/IV. However, patients with mildly reduced EF received less GDMT medications vs patients with moderately reduced EF and experienced less MR regression. Conclusion In patients with a recent diagnosis of HFrEF receiving contemporary GDMT, the majority with ≥moderate secondary MR and TR achieved regression of MR/TR, and the minority without significant baseline MR/TR developed ≥moderate regurgitation at follow-up.
When Anatomy Meets Hemodynamics: Interpreting CTA Planimetry of Aortic Valve Area

Circulation: Cardiovascular Imaging | February 17, 2026 | Volume: 19 | Issue: 3 | Pages: No page available

10.1161/circimaging.126.019572 | PMID 41700396

Prognostic Value of Artificial Intelligence–Enabled Electrocardiography–Derived Diastolic Dysfunction Grading and Trajectory in Patients Undergoing Transcatheter Aortic Valve Replacement

Journal of the American Heart Association | January 30, 2026 | Volume: 15 | Issue: 3 | Pages: No page available

10.1161/jaha.125.046558 | PMID 41614319

Background Artificial intelligence (AI)–enabled electrocardiography has emerged as a tool for detecting cardiac dysfunction. The prognostic relevance of AI‐enabled electrocardiography–derived diastolic dysfunction (DD) in patients undergoing transcatheter aortic valve replacement had not been assessed. Methods We analyzed 3197 patients undergoing transcatheter aortic valve replacement for severe aortic stenosis between 2010 and 2023 with baseline 12‐lead ECGs processed by a validated AI model to classify diastolic function (grades 0–3). Multivariable Cox models and nested model comparisons assessed associations with all‐cause mortality, including a prespecified analysis in patients with indeterminate echocardiographic grading. Trajectories were defined by change in AI‐enabled electrocardiography DD grade (<2 versus ≥2) from baseline to 30‐day or 1‐year follow‐up. Results At baseline, 21% had grade 3, 57% had grade 2, 8% had grade 1, and 14% had grade 0 AI‐enabled electrocardiography DD. Higher grades were associated with adverse cardiac remodeling and comorbidities. Over a median follow‐up of 3.4 years, grade 3 AI‐enabled electrocardiography DD independently predicted mortality (hazard ratio [HR], 1.80 [95% CI, 1.47–2.20]; P <0.001). AI‐enabled electrocardiography DD improved prognostic discrimination beyond clinical and echocardiographic measures (ΔHarrell concordance statistic, 0.016; Δ χ 2 =57; P <0.001). Among 1259 patients with indeterminate echocardiographic grading, AI‐enabled electrocardiography added prognostic value (ΔHarrell concordance statistic, 0.02; Δ χ 2 =13; P =0.006). Worsening or persistently high‐risk trajectories were associated with increased mortality (HRs, 1.45–1.80; all P <0.05). Conclusions AI‐enabled electrocardiography–derived DD independently predicts mortality after transcatheter aortic valve replacement, adds value beyond echocardiographic grading, and enables dynamic risk stratification through longitudinal tracking.
Natural history of asymptomatic moderate or severe aortic regurgitation: a systematic review and meta-analysis

Heart | November 17, 2025 | Volume: 112 | Issue: 12 | Pages: 646-657

10.1136/heartjnl-2025-326643 | PMID 41249036

Background The natural history of asymptomatic moderate or severe aortic regurgitation (AR) remains uncertain, with conflicting reports about its progression and surgical timing. We aimed to quantify adverse outcomes under conservative management and evaluate the association of aortic valve replacement/repair (AVR) with mortality. Methods Systematic searches (inception–July 2025) identified cohort studies of asymptomatic moderate/severe AR. Random-effects models estimated pooled incidence rates of adverse events; fixed-effects models were used for hazard ratios (HRs) of AVR vs conservative management. Results Twenty-seven studies (4720 patients; mean age 49 years; mean follow-up 3.9 years) were included. Pooled incidence rates per 100 person-years were 1.75 (95% CI 1.27 to 2.41) for all-cause mortality, 1.29 for cardiac death, 0.29 for sudden death, 4.30 for new symptoms and 7.01 for AVR. Asymptomatic low left ventricular ejection fraction occurred in only 0.9 per 100 person-years. Mortality rates were more than double those of the general population across age groups—2.45 (1.90 to 3.18) per 100 person-years for cohorts with mean age ≥50 years versus 0.59 (0.29 to 1.21) for younger cohorts. Early AVR was associated with lower mortality (pooled HR 0.33; 95% CI 0.30 to 0.37). Conclusion Asymptomatic moderate/severe AR carries significant excess mortality irrespective of age, contradicting its historically benign reputation. Given the rarity of asymptomatic LV dysfunction, earlier intervention guided by more sensitive markers of LV damage may improve outcomes, although heterogeneity and study quality warrant cautious interpretation. PROSPERO registration number CRD42024522683.
Valvular Heart Disease and Its Association With Death in Advanced Heart Failure

Journal of the American Heart Association | October 23, 2025 | Volume: 14 | Issue: 21 | Pages: No page available

10.1161/jaha.125.042875 | PMID 41128273

Background Valvular heart disease contributes to symptomatic heart failure, but its prevalence and prognostic significance in advanced heart failure is not well understood. Methods This retrospective population‐based cohort study included adult residents of Olmsted County, Minnesota, with advanced heart failure (2007–2018). Patients were classified by echocardiographic regurgitation and stenosis of aortic, mitral, tricuspid, and pulmonic valves at the time of advanced heart failure. We examined the associations of aortic stenosis, mitral regurgitation, and tricuspid regurgitation with risks of cardiovascular and all‐cause death through 2023 using Cox proportional hazards models. Results There were 936 patients with advanced heart failure (mean age, 76.9 years; 44.5% women, 43.4% with heart failure with preserved ejection fraction). Moderate or greater regurgitation was observed in 2.8% (n=26) of aortic, 26% (n=244) of mitral, 42% (n=389) of tricuspid, and 4.3% (n=40) of pulmonic valves, while moderate or greater stenosis was observed in 9.7% (n=91) of aortic and 1.8% (n=17) of mitral valves. No patients had clinically significant tricuspid or pulmonic stenosis. After adjustment for age, sex, left ventricular ejection fraction, right ventricular function, serum sodium, Charlson comorbidity index, body mass index, and systolic blood pressure, moderate and severe aortic stenosis were associated with increased cardiovascular death compared with patients without aortic stenosis (hazard ratio [HR], 1.42 [95% CI, 1.01–2.01]; and HR, 1.55 [95% CI, 1.02–2.36]), respectively. Conclusions Tricuspid regurgitation, mitral regurgitation, and aortic stenosis were the most observed valvular pathologies of moderate or greater severity in advanced heart failure. Only moderate or greater aortic stenosis was independently associated with cardiovascular death in advanced heart failure.
Prevalence and prognostic role of atrial fibrillation in chronic severe aortic regurgitation

Heart | July 16, 2025 | Volume: 112 | Issue: 1 | Pages: 46-52

10.1136/heartjnl-2025-325823 | PMID 40670146

Background Atrial fibrillation (AF) impacts management decisions in valvular heart disease but its significance in patients with chronic aortic regurgitation (AR) is not well established. Objectives To evaluate the prevalence and prognostic role of AF in patients with chronic, haemodynamically significant AR. Methods Adults with chronic ≥moderate-to-severe AR, from March 2004 to April 2019, were retrospectively identified. Those with acute AR, moderate or worse other valve disease or prior valve surgery were excluded. Patients with AF were identified based on 12-lead ECGs, 1-lead ECGs (showing AF for ≥30 s), or episodes recorded by implanted cardiac devices. Primary outcome was all-cause mortality. Cox regression models were used to assess associations with mortality: model 1 adjusted for age, symptoms (New York Heart Association class II–IV), Charlson Comorbidity Index, left ventricle (LV) end-systolic volume index and AF; model 2 added left atrial volume index and model 3 further added systolic pulmonary artery pressure. Results Of the 1006 included patients (age 59±18 years; 822 (82%) men), 446 (46%) had hypertension and 364 (36%) had a bicuspid aortic valve. AF was present in 161 (16%) patients at the time of ≥moderate-to-severe AR diagnosis. During a median follow-up of 1.6 years (IQR 0.2–6.2), AF was associated with an increased mortality risk in univariate and in all three multivariable models (HR 1.61 (95% CI 1.07 to 2.43), HR 2.21 (95% CI 1.31 to 3.72) and HR 2.06 (95% CI 1.21 to 3.52), respectively), including after propensity matching (HR 1.58 (95% CI 1.01 to 2.48)). Conclusions AF is present in one in six patients with chronic≥moderate-to-severe AR and is associated with an increased risk of mortality even after adjusting for measures of LV systolic and diastolic function. There is a need for future prospective studies to validate these findings and evaluate AF as a potential trigger for early surgery.
Association of Diuretic Dosage With Outcomes in Patients With Hemodynamically Significant Isolated Tricuspid Valve Regurgitation

Journal of the American Heart Association | July 14, 2025 | Volume: 14 | Issue: 14 | Pages: No page available

10.1161/jaha.124.039989 | PMID 40654247

Background Tricuspid valve surgery is recommended for severe isolated tricuspid regurgitation (TR) if symptoms persist despite optimal medical therapy. The definition of optimal therapy for TR is unclear beyond managing underlying conditions. Diuretics are the primary treatment for volume retention in TR, but it is unknown whether a “safe diuretic dose” exists for conservative management. We sought to evaluate the association between diuretic dose and outcomes. Methods Adult patients with ≥moderate–severe isolated TR were retrospectively identified from echocardiographic reports. Clinical and echocardiographic data were extracted from electronic medical records and manually reviewed. The primary end point was all‐cause mortality. Loop diuretic doses were converted to furosemide equivalent and categorized into 4 groups: <40 mg, 40 to 79 mg, 80 to 159 mg, and ≥160 mg daily. Results Of 1302 patients (age 72±13 years, 60% female), 565 (43%) had moderate–severe TR and 737 (57%) had severe TR. Median follow‐up was 8.7 (1.4, 14.0) years. Comorbidities increased with higher diuretic doses. A linear relationship between diuretic dose and mortality was observed in spline‐curve analysis. Hazard ratios (and CIs) for mortality adjusted for age, sex, coronary disease, chronic kidney disease, mild pulmonary hypertension, and New York Heart Association III/IV symptoms were 1.21 (0.96–1.53) ( P =0.12) for <40 mg, 1.50 (1.23–1.82) ( P <0.001) for 40 to 79 mg, 1.86 (1.46–2.37) ( P <0.001) for 80 to 159 mg, and 2.90 (2.18–3.88) ( P <0.001) for ≥160 mg furosemide equivalent. Any diuretic dose was associated with significant symptoms (New York Heart Association III–IV), with more patients experiencing symptoms at higher doses. Conclusion A daily loop diuretic dose ≥40 mg furosemide equivalent is associated with increased mortality and greater symptom severity in patients with TR.