Daily Cardiology Research Analysis
Analyzed 169 papers and selected 3 impactful papers.
Summary
Three impactful cardiology papers stood out today: a meta-analysis of randomized trials shows mineralocorticoid receptor antagonists reduce all-cause mortality in hypertension; a phase 2a randomized trial of the novel PDE5 inhibitor TPN171H demonstrates selective pulmonary vasodilation with significant PVR reduction in PAH; and a large real-world cohort shows adding an SGLT2 inhibitor to sacubitril-valsartan lowers heart failure hospitalization or death with acceptable safety.
Research Themes
- Antihypertensive therapy and mortality outcomes
- Targeted pulmonary vasodilation in PAH
- Real-world optimization of heart failure pharmacotherapy
Selected Articles
1. Mineralocorticoid receptor antagonists and mortality in hypertension: a systematic review and meta-analysis.
Across 17 randomized trials (n=25,498), MRAs were associated with a statistically significant reduction in all-cause mortality versus control (OR 0.91; absolute risk reduction 0.88%) over a median of ~20.5 months. Heterogeneity was negligible (I2=0%), supporting robustness of the mortality signal in predominantly hypertensive populations.
Impact: Clarifies a long-standing evidence gap by showing a mortality benefit of MRAs in hypertension, informing treatment algorithms beyond resistant hypertension.
Clinical Implications: Consider broader MRA use in hypertensive patients at elevated cardiovascular risk when potassium and renal function permit, with careful monitoring. Guideline updates may emphasize mortality benefit.
Key Findings
- Seventeen RCTs (n=25,498) included; 12 trials (n=24,426) reported mortality.
- MRAs reduced all-cause mortality vs control (OR 0.91, 95% CI 0.84–0.99) with an absolute risk reduction of 0.88%.
- Heterogeneity was negligible (I2=0%), and median follow-up for mortality analyses was 20.5 months.
Methodological Strengths
- Meta-analysis of randomized controlled trials with PROSPERO registration
- Low heterogeneity (I2=0%) and large aggregate sample size
Limitations
- Mortality was not always a primary endpoint across included trials
- Follow-up durations were relatively short to moderate (median ~12–20.5 months)
Future Directions: Dedicated hypertension RCTs with longer follow-up and mortality as the primary endpoint should validate the observed benefit and define subgroups most likely to benefit.
BACKGROUND: International guidelines differ in their recommendations for mineralocorticoid receptor antagonist (MRA) use in hypertension, as the effect on mortality is unclear. We meta-analyzed trial-level data to determine the association of MRA use with all-cause mortality in hypertension. METHODS: MEDLINE and EMBASE were searched for randomized clinical trials published from database inception through March 14, 2025, evaluating MRA use in trial populations with at least 85% prevalence of hypertension. The control groups consisted of placebo or usual care. Two reviewers independently screened and extracted data. Pooled estimates were calculated using random-effects and inverse variance models. The primary outcome was all-cause mortality. RESULTS: Seventeen randomized clinical trials were eligible for inclusion (n = 25 498), of which 12 trials reported mortality events (n = 24 426). The mean (±SD) baseline prevalence of hypertension was 95.0% (±5.0), mean baseline SBP was 134.8 (±9.0) mmHg, mean age was 64.1 (±5.3) years and 43.3% (n = 11 047) were female. The median duration of follow-up was 12 months (interquartile range 9-32 months). MRA use versus control was significantly associated with lower odds of all-cause mortality (12 trials, n = 24 426) (10.7 versus 11.6% over a median follow-up of 20.5 months; odds ratio (OR), 0.91 [95% confidence interval, 95% CI, 0.84-0.99]; absolute risk reduction, 0.88% [95% CI, 0.1-1.7]; I2 = 0.0%). CONCLUSION: In this meta-analysis of randomized clinical trials in predominantly hypertensive populations with substantial comorbidity, MRA use was significantly associated with lower all-cause mortality. Further dedicated trials in hypertensive populations, with longer follow-up and mortality as primary outcome, are warranted to confirm these findings. (PROSPERO; CRD420250601811).
2. Acute hemodynamic effects of TPN171H in pulmonary arterial hypertension: a randomized, controlled, phase 2a trial.
In a 60-patient phase 2a RCT, single-dose TPN171H 5 mg significantly reduced PVR versus placebo (−16.8%) and uniquely lowered the PVR/SVR ratio at multiple early time points, with no serious adverse events. The effect size was comparable to tadalafil on PVR but suggested greater pulmonary selectivity.
Impact: Introduces a novel PDE5 inhibitor candidate with signals of selective pulmonary vasodilation, addressing a key therapeutic need in PAH and warranting phase 3 evaluation.
Clinical Implications: While early-phase and hemodynamic-focused, findings support further clinical development of TPN171H as a potentially more pulmonary-selective vasodilator, which could translate into improved efficacy/tolerability profiles in PAH.
Key Findings
- TPN171H 5 mg reduced PVR versus placebo by −16.8% (95% CI −29.1 to −4.5; p=0.008).
- Only TPN171H 5 mg, not tadalafil, significantly reduced PVR/SVR ratio at 2, 3, and 5 hours.
- No serious adverse events were reported across randomized groups during 24-hour assessment.
Methodological Strengths
- Randomized, controlled, dose-ranging phase 2a design with active comparator arms
- Direct invasive hemodynamic endpoints (PVR and PVR/SVR)
Limitations
- Small sample size and short (24-hour) assessment window focused on surrogate endpoints
- Not powered for clinical outcomes or longer-term safety
Future Directions: Proceed to adequately powered trials with longer follow-up to assess clinical outcomes (6MWD, NT-proBNP, WHO class) and confirm pulmonary selectivity and safety.
Pulmonary arterial hypertension (PAH) has a poor prognosis despite available treatments. TPN171H, structurally modified from traditional Chinese medicine (Epimedium), was reported to have a high affinity for phosphodiesterase type 5 and exhibited anti-inflammatory and vasodilatory effects in preclinical studies. This phase 2a randomized trial (NCT04483115) evaluated the hemodynamic effects and safety of TPN171H in PAH. Sixty patients with PAH were randomly assigned to receive placebo, TPN171H (2.5, 5, or 10 mg) or tadalafil (20 or 40 mg) and evaluated for hemodynamic changes for 24 h. The primary endpoint was the maximum change (%) in pulmonary vascular resistance (PVR) from baseline. The key secondary endpoint was the change (%) in PVR to systemic vascular resistance (SVR) ratio at each observation point from baseline. Compared to the placebo group, the least square mean differences in the maximum change in PVR were -16.8% (95% CI, -29.1 to -4.5, p = 0.008) in TPN171H 5 mg, -15.4% (95% CI, -28.2 to -2.7, p = 0.019) in tadalafil 20 mg, and -13.3% (95% CI, -25.6 to -0.9, p = 0.036) in the tadalafil 40 mg group. Moreover, TPN171H 5 mg, but none of the tadalafil doses, showed a significant reduction in PVR/SVR ratio at 2 h (p = 0.026), 3 h (p = 0.030), and 5 h (p = 0.046) compared to the placebo group. No serious adverse events occurred. TPN171H 5 mg demonstrated favorable acute hemodynamic effects and an acceptable short-term safety profile in this exploratory trial, supporting further evaluation in adequately powered trials.
3. Effectiveness and Safety of SGLT2 Inhibitor Initiation in Sacubitril-Valsartan Users with Heart Failure: A Population-Based Cohort Study.
In 5,000 matched pairs of older HF patients on sacubitril-valsartan, initiating an SGLT2 inhibitor reduced the composite of heart failure hospitalization or all-cause mortality (HR 0.71; 1-year absolute risk 13.9% vs 19.2%). Safety was generally favorable, with increased genital infections but no excess hypotension, falls, UTIs, or DKA; AKI risk decreased among those with diabetes.
Impact: Provides high-quality real-world evidence supporting additive benefit and safety of combining SGLT2 inhibitors with sacubitril-valsartan in routine practice.
Clinical Implications: Supports an early, layered approach to guideline-directed medical therapy in HF by adding SGLT2 inhibitors to ARNI therapy, with attention to genital infections and routine renal monitoring.
Key Findings
- SGLT2i initiation lowered HHF or all-cause mortality (HR 0.71; 1-year absolute risk 13.9% vs 19.2%).
- Genital infection risk increased (HR 2.36), but hypotension, falls, UTIs, and DKA did not increase.
- AKI risk decreased in those with diabetes (HR 0.78) but not in non-diabetes, suggesting heterogeneity by glycemic status.
Methodological Strengths
- Target-trial emulation with time-conditional propensity score matching
- Large, population-based dataset with prespecified effectiveness and safety outcomes
Limitations
- Observational design susceptible to residual confounding despite robust matching
- Older (≥66 years) cohort may limit generalizability to younger HF patients
Future Directions: Assess effectiveness across HF phenotypes, explore optimal sequencing/titration, and evaluate patient-centered outcomes and cost-effectiveness in broader health systems.
BACKGROUND: Large-scale real-world evidence regarding outcomes of sodium-glucose cotransporter-2 inhibitors (SGLT2i) initiation added to sacubitril-valsartan is currently limited. We aim to investigate effectiveness and safety of SGLT2i initiation among older sacubitril-valsartan users with heart failure in routine clinical practice. METHODS: This prevalent new-user cohort study used linkable administrative data in Ontario, Canada, to emulate a target trial. In sacubitril-valsartan users with heart failure aged ≥66 years, SGLT2i initiators were matched on time-conditional propensity scores to non-initiators (October 2019 to June 2024). The primary effectiveness outcome was a composite of hospitalization for heart failure (HHF) or all-cause mortality. We also studied safety outcomes, including acute kidney injury (AKI), genital infection, urinary tract infection (UTI), falls, hospitalization for hypotension, diabetic ketoacidosis (DKA), and hypoglycemia. RESULTS: Among 5,000 matched pairs, SGLT2i initiation was associated with lower HHF or all-cause mortality (hazard ratio [HR] 0.71, 95% confidence interval 0.64-0.78; 1-year absolute risk: 13.9% versus 19.2%). SGLT2i initiation was associated with a higher genital infection risk (2.36, 1.58-3.51; 1.8% versus 0.7%) but not with higher rates of falls, hospitalization for hypotension, or UTI. DKA was uncommon among SGLT2i users with diabetes as were hypoglycemic events among SGLT2i users without diabetes. SGLT2i initiation showed lower AKI among those with diabetes (0.78, 0.66-0.94) but not among those without diabetes (1.01, 0.66-0.94; HR homogeneity: p=0.035). CONCLUSIONS: This observational real-world evidence study supports effectiveness of SGLT2i among older sacubitril-valsartan users with heart failure, and suggests no increase in the safety outcomes studied, except genital infection.