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Nishimura, Rick A

0000-0003-4651-9740

Mayo Clinic

Mayo Clinic

Citations 12

Redefining Severe Aortic Stenosis in Symptomatic Patients: The Weakness of Using Simple Cutoffs

Circulation | September 8, 2026 | Volume: 154 | Issue: 10 | Pages: 873-875

10.1161/circulationaha.126.081126 | PMID 42709915

Evolution and Transformation of Hypertrophic Cardiomyopathy From a High Risk to a Treatable Low Mortality Disease With Contemporary Clinical Research Strategies

Journal of the American Heart Association | March 25, 2026 | Volume: 15 | Issue: 12 | Pages: No page available

10.1161/jaha.125.047462 | PMID 41878858

Once considered rare and essentially untreatable with a grim prognosis and reduced life expectancy, hypertrophic cardiomyopathy (HCM) has evolved substantially over 6 decades. Ultimately, HCM has become a contemporary global disease with pharmacologic and interventional options offering effective personalized treatment for all adverse disease pathways. Striking reduction in HCM‐related mortality to ≤0.5%/year in optimally treated cohorts is now comparable to that expected in the US general population, lower than most other disease risks to living, and 10‐fold less than the earliest estimates. The few deaths directly related to HCM are now largely attributable to advanced (end‐stage) heart failure in patients with nonobstructive HCM. Determinants of this transformation to a lower risk disease are evident in hallmark clinical inflection points and breakthroughs, including dedicated HCM programs assembling large clinical databases in which focused (and unfunded) physician‐investigators have derived data directly from patients in clinical practice. Evidence‐based observational studies report emergence of contemporary treatment strategies enhancing survival: implantable defibrillators prevent arrhythmic sudden death globally with 95% sensitive patient selection using an American Heart Association/American College Cardiology risk stratification algorithm; low‐risk, high‐benefit surgical myectomy reverses outflow obstruction and heart failure in >90% with a long‐term survival benefit; and aggressive anticoagulation has reduced embolic strokes. Recent novel pharmacologic alternatives (cardiac myosin inhibitors) are proving effective in relieving obstruction/symptom burden and changing disease management. These principles and time‐tested patient‐centered research strategies uniquely tailored to the heterogeneous HCM clinical spectrum are pivotal in providing practice insights, offering a vulnerable population more optimistic prognosis including opportunity to achieve normal longevity not available to prior generations of patients.
Mitral Annulus Calcium Score in Patients With Calcific Mitral Stenosis Undergoing Invasive Hemodynamic Assessment

Journal of the American Heart Association | January 19, 2024 | Volume: 13 | Issue: 3 | Pages: No page available

10.1161/jaha.123.030540 | PMID 38240203

Background Aortic valve calcium score is associated with hemodynamic severity of aortic stenosis. Whether this association is present in calcific mitral stenosis remains unknown. Methods and Results This study was a retrospective analysis of consecutive patients with mitral stenosis secondary to mitral annular calcification (MAC) undergoing transseptal catheterization. All patients underwent invasive mitral valve assessment via direct left atrial and left ventricular pressure measurement. Computed tomography within 1 year of cardiac catheterization and with adequate visualization of the mitral annulus was included. MAC calcium score quantification by Agatston method was obtained offline using dedicated software (Aquarius, TeraRecon, V.4). Median patient age was 66.9±11.2 years, 47% of patients were women, 50% had coronary artery disease, 40% had atrial fibrillation, 47% had prior cardiac surgery, and 33% had prior chest radiation. Median diastolic mitral valve gradient was 9.4±3.4 mm Hg on echocardiography and 8.5±4 mm Hg invasively. Invasive median mitral valve area using the Gorlin formula was 1.87±0.9 cm 2 . Median MAC calcium score for the cohort was 7280±7937 Hounsfield units. MAC calcium score correlated with the presence of atrial fibrillation ( P =0.02) but was not associated with other comorbidities. There was no correlation between MAC calcium score and mitral valve area ( r =0.07; P =0.6) or mitral valve gradient ( r =−0.03; P =0.8). Conclusions MAC calcium score did not correlate with invasively measured mitral valve gradient and mitral valve area in patients with MAC‐related mitral stenosis, suggesting that calcium score should not be used as a surrogate for invasive hemodynamic parameters.
Hemodynamic Predictors of Outcome Following Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy

Circulation: Cardiovascular Interventions | August 15, 2023 | Volume: 16 | Issue: 8 | Pages: No page available

10.1161/circinterventions.123.013068 | PMID 37582173

BACKGROUND: Alcohol septal ablation (ASA) is a minimally invasive treatment for drug-refractory obstructive hypertrophic cardiomyopathy. Detailed assessment of pressure changes and predictors of mortality and procedure success are not well defined. METHODS: This is a single-center study evaluating pressure changes and predictors of mortality and procedure success in transseptal ASA. Survival analysis and predictors of mortality were assessed using the Kaplan-Meier analysis and Cox regression, respectively. RESULTS: A total of 156 patients were included (mean age, 67.3 years; 46.8% women). Left atrial (LA) pressure and left ventricular outflow tract (LVOT) gradient decreased, whereas aortic pulse pressure (PP) increased post-ASA. Patients with lower baseline mean LA pressure (<median, 19 mm Hg), LVOT gradient reduction >82% (gradient change median), and PP increase >19% (PP change median) had superior survival. On Cox univariable regression, baseline mean LA pressure >median (19 mm Hg; hazard ratio [HR], 2.09 [95% CI, 1.05–4.18]; P =0.036), residual LVOT gradient (HR, 1.02 [95% CI, 1.01–1.03]; P =0.003), and LVOT gradient percent reduction <median (82%; HR, 2.92 [95% CI, 1.46–5.83]; P =0.002) were predictors of mortality. When adjusting for age and sex, baseline LA v wave >median (28 mm Hg; HR, 2.36 [95% CI, 1.17–4.76]; P =0.016), baseline mean LA pressure >median (19 mm Hg; HR, 2.70 [95% CI, 1.33–5.50]; P =0.006), percentage reduction in gradient <median (82%; HR, 2.74 [CI, 1.37–5.50]; P =0.005), and percentage increase in PP <median (19.3%; HR, 2.09 [CI, 1.05–4.16]; P =0.035) predicted survival free of all-cause mortality. CONCLUSIONS: ASA is associated with an acute decrease in the LVOT gradient and LA pressures and increase in aortic PP. Mean LA pressure, percentage decrease in LVOT gradient, and increase in PP are strong predictors of survival free of all-cause mortality following ASA and are important variables for procedural guidance.
Impact of Race and Ethnicity on Use and Outcomes of Septal Reduction Therapies for Obstructive Hypertrophic Cardiomyopathy

Journal of the American Heart Association | December 24, 2022 | Volume: 12 | Issue: 1 | Pages: No page available

10.1161/jaha.122.026661 | PMID 36565202

Background Information on impact of race and ethnicity on use and early outcomes of septal reduction therapies (SRTs) for obstructive hypertrophic obstructive cardiomyopathy are limited. Methods and Results Using the National Inpatient Sample from January 2012 through December 2019, we identified all adult admissions with a primary diagnosis of obstructive hypertrophic cardiomyopathy and those undergoing SRT. Predictors of receiving SRT and outcomes including in‐hospital mortality, complications, and resource use were evaluated in racial and ethnic groups. Among a total of 18 895 adult admissions with obstructive hypertrophic cardiomyopathy, SRT was performed in 7255 (38.4%) admissions. Septal myectomy was performed in 4930 (26.1%), while alcohol septal ablation was performed in 2325 (12.3%). In adjusted analysis, Black patient (versus White patient adjusted odds ratio, 0.65 [95% CI, 0.57–0.73]; P <0.001) and Hispanic patient admissions (versus White adjusted odds ratio, 0.78 [95% CI, 0.66–0.92]; P =0.003) were less likely to receive SRT. Among admissions undergoing SRT, in‐hospital mortality was significantly higher for Hispanic (adjusted odds ratio, 3.38 [95% CI, 1.81–6.30], P <0.001) and other racial and ethnic groups (adjusted odds ratio 2.02 [95% CI, 1.00–4.11]; P =0.05) compared with White patient admissions, whereas Black patient admissions had comparable mortality. Black, Hispanic, and other ethnic group patients had higher rates of SRT complications and more frequent dismissals to acute care facilities. Conclusions Among obstructive hypertrophic cardiomyopathy hospitalizations, minoritized racial groups were less likely to receive SRT. Importantly, hospitalizations of Hispanic and other ethnic patients undergoing SRT had significantly higher in‐hospital mortality and complication rates. Further studies with granular echocardiographic information to assess indications for SRT are needed to better understand these differences.
Invasive Hemodynamic Predictors of Survival in Patients With Mitral Stenosis Secondary to Mitral Annular Calcification

Journal of the American Heart Association | May 16, 2022 | Volume: 11 | Issue: 10 | Pages: No page available

10.1161/jaha.121.023107 | PMID 35574960

Background The aim of this study was to establish prognostic hemodynamic parameters in patients with mitral stenosis secondary to mitral annular calcification. Methods and Results A retrospective cohort of 105 patients undergoing transseptal catheterization for hemodynamic evaluation of mitral annular calcification–related mitral stenosis between 2004 and 2020 was studied. Mitral valve gradient (MVG) and mitral valve area (MVA; calculated by the Gorlin formula) were measured using direct left atrial and left ventricular pressures. The median age of the patients was 70.3 years (58.4–76.7 years), and 53.3% were women. The median MVA was 1.7 cm 2 (1.3–2.3 cm 2 ) and MVG was 7.3 mm Hg (5.3–10.3 mm Hg); left ventricular end‐diastolic pressure was 17.6±28.3 mm Hg. During a median of 2.1 years (0.7–4.5 years), there were 63 deaths; 1‐ and 5‐year survival were 76% and 40%, respectively. There was no association between left ventricular end‐diastolic pressure and survival. After adjusting for age and comorbidities, both MVA (hazard ratio [HR], 0.50 per cm 2 ; 95% CI, 0.34–0.73) and MVG (HR, 1.1 per mm Hg; 95% CI, 1.05–1.20) were independent predictors of death. Atrial fibrillation was also independently associated with mortality. When added to a combined model, MVA remained associated with death (HR, 0.51 per cm 2 ; 95% CI, 0.33–0.79) while MVG was not. Conclusions In patients with mitral annular calcification–related mitral stenosis, survival was poor. MVA and MVG were independently associated with death, but MVA was a better predictor of outcomes.
Reduction in Right Atrial Pressures Is Associated With Hemodynamic Improvements After Transcatheter Edge-to-Edge Repair of the Tricuspid Valve

Circulation: Cardiovascular Interventions | November 24, 2021 | Volume: 14 | Issue: 12 | Pages: No page available

10.1161/circinterventions.121.010557 | PMID 34814697

Background: Investigational transcatheter edge-to-edge repair (TEER) for severe tricuspid regurgitation (TR) has shown promise as an alternative to surgery, but factors influencing outcomes, optimal patient selection, and procedural timing remain incompletely defined. Given the limitations of determining TR severity by conventional echocardiography, our objectives were to determine whether invasive right atrial (RA) pressures performed during the procedure are related to patient outcomes. Methods: This study was a retrospective review of patients who underwent off-label tricuspid TEER using MitraClip (Abbott Vascular, Menlo Park, CA) for significant TR at a single institution. Intraprocedural mean RA pressure, RA peak V-wave, RA pressure nadir, and systolic increase in RA pressure (XV height) were recorded. Results: Thirty-eight patients underwent tricuspid TEER; 33 underwent concomitant mitral TEER for mitral regurgitation. The study cohort was 39% female with a mean age of 78.6±14.3 years. Median follow-up was 339 days (interquartile range, 100–601). Any reduction in mean RA pressure, RA peak V-wave, RA nadir, and XV height occurred in 74%, 82%, 45%, and 87% of patients, respectively. At 1 year, event-free survival was 47%. Postprocedure XV height correlated with TR severity as determined by echocardiography ( P <0.0001). The highest quartile of postprocedure XV height (>8 mm Hg) had worse event-free survival compared with those who had concluding XV height ≤8 mm Hg ( P =0.02). Attainment of a concluding XV height less than or equal to median value was associated with a lower creatinine the next day (1.27±0.47 versus 1.64±0.47 mg/dL, P =0.04). Conclusions: Intraprocedural XV height correlates with TR severity after tricuspid TEER, and lower concluding pressures are associated with improved outcomes. Analysis of RA pressures may serve as a complementary tool for the evaluation of disease severity and procedural guidance.
Measuring Pressure Gradients After Transcatheter Aortic Valve Implantation: Rethinking the Bernoulli Principle

Journal of the American Heart Association | September 29, 2021 | Volume: 10 | Issue: 19 | Pages: No page available

10.1161/jaha.121.022515 | PMID 34585620

Predictors of Use and Outcomes of Mechanical Valve Replacement in the United States (2008–2017)

Journal of the American Heart Association | June 21, 2021 | Volume: 10 | Issue: 9 | Pages: No page available

10.1161/jaha.120.019929 | PMID 33870704

Background Contemporary nationwide data on the use, predictors, and outcomes of mechanical valve replacement in patients less than 70 years of age are limited. Methods and Results We identified hospitalizations for aortic valve replacement (AVR) or mitral valve replacement (MVR) in the Nationwide Inpatient Sample between January 1, 2008, and December 31, 2017. The study's end points included predictors of mechanical valve replacement and risk‐adjusted in‐hospital mortality. Among 253 100 hospitalizations for AVR, the use rate of mechanical prosthesis decreased from 45.3% in 2008 to 17.0% in 2017. Among 284 962 hospitalizations for MVR, mechanical prosthesis use decreased from 59.5% in 2008 to 29.2% in 2017 ( P for trend<0.001). In multilogistic regression analyses, female sex, prior sternotomy, prior defibrillator, and South/West geographic location were predictive of mechanical valve use. The presence of bicuspid valve was a negative predictor of mechanical AVR (odds ratio [OR], 0.68; 95% CI, 0.66–0.69; P <0.001), whereas mitral stenosis was associated with higher mechanical MVR (OR, 1.28; 95% CI, 1.22–1.33; P <0.001). Unadjusted in‐hospital mortality decreased over time with AVR but not with MVR, regardless of prosthesis choice. Using years 2008 and 2009 as a reference, risk‐adjusted mortality also decreased over time with AVR but did not decrease after MVR. Conclusions There is a substantial decline in the use of mechanical valve replacement among patients aged ≤70 years in the United States. Long‐term durability data on bioprosthetic valve replacement are needed to better define the future role of mechanical valves in this age group.
Hemodynamic Benefits From Left Atrial Pacing to Treat Interatrial Conduction Delay Following Atrial Fibrillation Ablation

Circulation: Heart Failure | April 30, 2021 | Volume: 14 | Issue: 5 | Pages: No page available

10.1161/circheartfailure.120.008191 | PMID 33926194