3D Transthoracic Echocardiography for Semiautomated Analysis of the Tricuspid Annulus: Validation and Normal Values.

BACKGROUND: The expansion of tricuspid valve (TV) interventions has underscored the need for accurate and reproducible 3D transthoracic echocardiography (TTE) tools for evaluating the tricuspid annulus (TA) and for 3D normal values of this structure. We aimed to: develop new semi-automated software for 3DTTE analysis of the TA, compare its accuracy and reproducibility against multiplanar reconstruction (MPR) reference, and determine normative values. METHODS: 3DTTE images of 113 patients with variable degrees of tricuspid regurgitation were analyzed using the new semi-automated software and conventional MPR methodology (as the reference standard), each by 3 independent readers. For each measured parameter, inter-technique agreement was assessed using linear regression and Bland-Altman analyses, and inter-reader variability using intraclass correlation (ICC) and coefficients of variation (CoV). Additionally, 3DTTE datasets of 789 subjects from the WASE Study were analyzed using this new software to determine normal values for each TA parameter. RESULTS: Semi-automated measurements showed excellent agreement with MPR reference values for all TA measurements: high correlations (all r-values >0.8) and minimal biases. All measurements were more reproducible than with MPR: higher ICC values (0.94-0.96 vs 0.82-0.90), and lower CoV (5-12% vs 8-18%). Sex- and age-related differences were identified in 3D normal values of most TA parameters. Dynamic analysis showed that TA parameters vary throughout the cardiac cycle, reaching minimal values at end-systole and maximum values in late diastole. CONCLUSION: Novel software for semi-automated analysis of the TA geometry and dynamics provides accurate and reproducible measurements. Normal values of TA dimensions, parsed by sex and age, are hereby reported.

Assessing Right Atrial Size in Patients with Tricuspid Regurgitation: Importance of the Right Ventricular-Focused View.

AIMS: To assess the accuracy of measuring the right atrial volume (RAV) using two-dimensional echocardiography (2DE) in a right ventricular focused (RVF) view compared to the conventional apical 4-chamber (4Ch) view in patients with secondary tricuspid regurgitation (STR). We also compared the clinical correlates of the measures obtained using different methods. METHODS AND RESULTS: The accuracy of RAV measurements obtained from 2DE- 4Ch and RVF views in 384 patients with STR were compared using three-dimensional echocardiography (3DE) as a reference. We used the analysis of variance to test the differences among RAVs obtained from the different 2DE and 3DE acquisitions and the receiving operating characteristics (ROC) curves to evaluate the association with the composite endpoint of hospitalization for heart failure or death. Compared to 3DE, RAV was significantly more underestimated when measurements were obtained from 4Ch rather than RVF (-24% vs. -14%, respectively, p<0.001 for both). RAV underestimation in 4Ch and RVF view was relatively larger in lower grades of STR (-28% vs. -17% in mild, -23% vs. -14% in moderate, and -19% vs. -11% in severe STR, p=0.001), and in the atrial compared to ventricular (-28% vs. -22%; p=0.002) STR. RAV measured by 3DE and RVF showed the highest area under the curve (AUC=0.67 for 3DE vs 0.64 for RVF, p=0.05), while 4Ch was significantly less related to the outcomes (AUC: 0.61, p=0.021 vs 3DE RAV). CONCLUSIONS: In patients with STR, the use of RVF view improved the accuracy of 2DE RAV measurement as compared to the conventional 4Ch-derived measurements.

Advances in the Assessment of Patients With Tricuspid Regurgitation: A State-of-the-Art Review on the Echocardiographic Evaluation Before and After Tricuspid Valve Interventions.

Tricuspid regurgitation (TR) can have a significant impact on the health and mortality of a patient. Unfortunately, many patients with advanced right-sided heart failure are not referred for isolated tricuspid valve (TV) surgery in a timely manner. This delayed referral has resulted in a high in-hospital mortality rate and significant undertreatment. Fortunately, transcatheter TV intervention (TTVI) has emerged as a safe and effective alternative to surgery, successfully reducing TR severity and improving patients' quality of life. Current guidelines emphasize the importance of assessing TR severity and its impact on the right heart chambers for selecting the appropriate intervention. However, the echocardiographic assessment of both right chambers and TV anatomy, along with TR severity, poses specific challenges, leading to the underestimation of TR severity. Recently, three-dimensional echocardiography has become crucial to enhance the characterization of TR severity. Moreover, it is essential to evaluate residual TR after TTVI to gauge the intervention's success and predict the patient's prognosis. This review provides a thorough evaluation of the echocardiographic parameters used to assess TR severity before and after TTVI. It presents a critical analysis of the accuracy and reliability of these parameters, highlighting their strengths and limitations to establish standardized diagnostic criteria and treatment protocols for TR, which will inform clinical decision-making and improve patient outcomes.

Significant Disagreement Between Conventional Parameters and 3D Echocardiography-Derived Ejection Fraction in the Detection of Right Ventricular Systolic Dysfunction and Its Association With Outcomes.

AIMS: Conventional echocardiographic parameters such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and free-wall longitudinal strain (FWLS) offer limited insights into the complexity of right ventricular (RV) systolic function, while 3D echocardiography-derived RV ejection fraction (RVEF) enables a comprehensive assessment. We investigated the discordance between TAPSE, FAC, FWLS, and RVEF in RV systolic function grading and associated outcomes. METHODS: We analyzed two- and three-dimensional echocardiography data from 2 centers including 750 patients followed up for all-cause mortality. Right ventricular dysfunction was defined as RVEF <45%, with guideline-recommended thresholds (TAPSE <17 mm, FAC <35%, FWLS >-20%) considered. RESULTS: Among patients with normal RVEF, significant proportions exhibited impaired TAPSE (21%), FAC (33%), or FWLS (8%). Conversely, numerous patients with reduced RVEF had normal TAPSE (46%), FAC (26%), or FWLS (41%). Using receiver-operating characteristic analysis, FWLS exhibited the highest area under the curve of discrimination for RV dysfunction (RVEF <45%) with 59% sensitivity and 92% specificity. Over a median 3.7-year follow-up, 15% of patients died. Univariable Cox regression identified TAPSE, FAC, FWLS, and RVEF as significant mortality predictors. Combining impaired conventional parameters showed that outcomes are the worst if at least 2 parameters are impaired and gradually better if only one or none of them are impaired (log-rank P < .005). CONCLUSION: Guideline-recommended cutoff values of conventional echocardiographic parameters of RV systolic function are only modestly associated with RVEF-based assessment. Impaired values of FWLS showed the closest association with the RVEF cutoff. Our results emphasize a multiparametric approach in the assessment of RV function, especially if 3D echocardiography is not available.

Timing and Patient Position During Cuff Blood Pressure Measurement Affect Myocardial Work Parameters Measured by Echocardiography.

BACKGROUND: Although cuff blood pressure measurement is a critical parameter to calculate myocardial work noninvasively, there is no recommendation about when and how to measure it. Accordingly, we sought to evaluate the effects of the timing during the echo study and the patient's position on the scanning bed during the cuff blood pressure measurement on myocardial work parameter calculations. METHODS: One hundred one consecutive patients (44 women, 66 ± 14 years) undergoing clinically indicated echocardiography were prospectively enrolled. During the echocardiographic study, we measured the cuff blood pressure 4 times, using a fully automatic digital blood pressure monitor applied to the right and left arm in the same position throughout the study: BP1, before the start of the echo study, with the patient lying in the supine position; BP2, after positioning the patients on their left side to start the echo study; BP3, at the time of the acquisition of the 3 apical views (4- and 2-chamber and long-axis) used to measured left ventricular global longitudinal strain; and BP4, at the end of the echo study with the patient again in the supine position. RESULTS: Systolic blood pressureat BP1 was 147 ± 21 mm Hg. Between BP1 and BP2, it dropped by 17 ± 9 mm Hg (P < .05). Systolic blood pressure at BP3 was significantly lower than BP2 (130 ± 20 mm Hg vs 122 ± 18 mm Hg, P < .05), and at BP4 was significantly lower than at BP1 (-9 ± 13 mm Hg, P < .05). The average global longitudinal strain was -16% ± 3%. Accordingly, the global work index was 1,929 ± 441 mm Hg% at BP1, dropped to 1,717 ± 421 at BP2, decreased to 1,602 ± 351 mm Hg% at BP3, and increased to 1,815 ± 386 mm Hg% at BP4 (P < .001). CONCLUSIONS: The timing during the echocardiography study and the patient's position on the scanning bed are critical determinants of the measured cuff systolic blood pressure and the resulting values of myocardial work parameters.

Complex percutaneous transcatheter closure of incomplete surgical ligation of the left atrial appendage: a case report.

Background: Incomplete surgical left atrial appendage (LAA) closure, in the form of incompletely surgically ligated LAA (ISLL), increases thrombo-embolic risk in patients with atrial fibrillation (AF). Although its management is not standardized, the percutaneous closure of ISLL could be an alternative in patients with contraindication for anticoagulants. We present the case of a percutaneous transcatheter LAA device implantation in a patient with AF and ISLL, complicated by severe anaemia. Case summary: A 83-year-old woman, with permanent AF and a history of previous surgical LAA ligation, was referred to our hospital for fatigue and worsening dyspnoea. Laboratory tests showed severe microcytic anaemia, with a haemoglobin level of 4.9 g/dL (normal reference: 13.8-18.0 g/dL). Oesophagogastroduodenoscopy and colonoscopy excluded signs of either recent or ongoing haemorrhage. After achieving clinical improvement by haemotransfusions, we performed a transoesophageal echocardiography that showed an ISLL with a narrow neck of 5 mm. Since the patient had high thrombo-embolic and haemorrhagic risk (CHA2DS2-VASc risk score of 4 and a HAS-BLED score of 4), we decided to discontinue anticoagulant therapy and perform elective percutaneous transcatheter LAA occlusion (LAAO) with an Amplatzer Amulet device. Patient was discharged in good clinical status. After three months, the stability of haemoglobin level and the absence of device thrombosis allowed the discontinuation of antithrombotic therapy. Discussion: We described the first experience of percutaneous ISLL closure with Amulet device (Abbott Vascular, Santa Clara, CA, USA), a commercially available device for LAAO. The procedure was feasible and safe, without long-term complications.

Peak atrial longitudinal strain and risk stratification in moderate and severe aortic stenosis.

AIMS: We sought to investigate the association of left atrial strain with the outcome in a large cohort of patients with at least moderate aortic stenosis (AS). METHODS AND RESULTS: We analysed 467 patients (mean age 80.6 ± 8.2 years; 51% men) with at least moderate AS and sinus rhythm. The primary study endpoint was the composite of all-cause mortality and hospitalizations for heart failure. After a median follow-up of 19.2 (inter-quartile range 12.5-24.4) months, 96 events occurred. Using the receiver operator characteristic curve analysis, the cut-off value of peak atrial longitudinal strain (PALS) more strongly associated with outcome was <16% {area under the curve (AUC) 0.70 [95% confidence interval (CI): 0.63-0.78], P < 0.001}. The Kaplan-Meier curves demonstrated a higher rate of events for patients with PALS < 16% (log-rank P < 0.001). On multivariable analysis, PALS [adjusted HR (aHR) 0.95 (95% CI 0.91-0.99), P = 0.017] and age were the only variables independently associated with the combined endpoint. PALS provided incremental prognostic value over left ventricular (LV) global longitudinal strain, LV ejection fraction, and right ventricular function. Subgroup analysis revealed that impaired PALS was also independently associated with outcome in the subgroups of paucisymptomatic patients [aHR 0.98 (95% CI 0.97-0.98), P = 0.048], moderate AS [aHR 0.92, (95% CI 0.86-0.98), P = 0.016], and low-flow AS [aHR 0.90 (95% CI 0.83-0.98), P = 0.020]. CONCLUSION: In our patients with at least moderate AS, PALS was independently associated with outcome. In asymptomatic patients, PALS could be a potential marker of sub-clinical damage, leading to better risk stratification and, potentially, earlier treatment.

Right Atrial Remodeling and Outcome in Patients with Secondary Tricuspid Regurgitation.

BACKGROUND: In patients with secondary tricuspid regurgitation (STR), right atrial remodeling (RAR) is a proven marker of disease progression. However, the prognostic value of RAR, assessed by indexed right atrial volume (RAVi) and reservoir strain (RAS), remains to be clarified. Accordingly, the aim of our study is to investigate the association with outcome of RAR in patients with STR. METHODS: We enrolled 397 patients (44% men, 72.7 ± 13 years old) with mild to severe STR. Complete two-dimensional and speckle-tracking echocardiography analysis of right atrial and right ventricular (RV) size and function were obtained in all patients. The primary end point was the composite of death from any cause and heart failure hospitalization. RESULTS: After a median follow-up of 15 months (interquartile range, 6-23), the end point was reached by 158 patients (39%). Patients with RAS <13% and RAVi >48 mL/m2 had significantly lower survival rates compared to patients with RAS ≥13% and RAVi ≤48 mL/m2 (log-rank P < .001). On multivariable analysis, RAS <13% (hazard ratio, 2.11; 95% CI, 1.43-3.11; P < .001) and RAVi > 48 mL/m2 (hazard ratio, 1.49; 95% CI, 1.01-2.18; P = .04) remained associated with the combined end point, even after adjusting for RV free-wall longitudinal strain, significant chronic kidney disease, and New York Heart Association class. Secondary tricuspid regurgitation excess mortality increased exponentially with values of 18.2% and 51.3 mL/m2 for RAS and RAVi, respectively. In nested models, the addition of RAS and RAVi provided incremental prognostic value over clinical, conventional echocardiographic parameters of RV size and function and RV free-wall longitudinal strain. CONCLUSIONS: In patients with STR, RAR was independently associated with mortality and heart failure hospitalization. Assessment of RAR could improve risk stratification of patients with STR, potentially identifying those who may benefit from optimization of medical therapy and a closer follow-up.

Clinical Impact of the Volumetric Quantification of Ventricular Secondary Mitral Regurgitation by Three-Dimensional Echocardiography.

BACKGROUND: The assessment of ventricular secondary mitral regurgitation (v-SMR) severity through effective regurgitant orifice area (EROA) and regurgitant volume (RegVol) calculations using the proximal isovelocity surface area (PISA) method and the two-dimensional echocardiography volumetric method (2DEVM) is prone to underestimation. Accordingly, we sought to investigate the accuracy of the three-dimensional echocardiography volumetric method (3DEVM) and its association with outcomes in v-SMR patients. METHODS: We included 229 patients (70 ± 13 years, 74% men) with v-SMR. We compared EROA and RegVol calculated by the 3DEVM, 2DEVM, and PISA methods. The end point was a composite of heart failure hospitalization and death for any cause. RESULTS: After a mean follow-up of 20 ±11 months, 98 patients (43%) reached the end point. Regurgitant volume and EROA calculated by 3DEVM were larger than those calculated by 2DEVM and PISA. Using receiver operating characteristic curve analysis, both EROA (area under the curve, 0.75; 95% CI, 0.68-0.81; P = .008) and RegVol (AUC, 0.75; 95% CI, 0.68-0.82; P = .02) measured by 3DEVM showed the highest association with the outcome at 2 years compared to PISA and 2DEVM (P < .05 for all). Kaplan-Meier analysis demonstrated a significantly higher rate of events in patients with EROA ≥ 0.3 cm2 (cumulative survival at 2 years: 28% ± 7% vs 32% ± 10% vs 30% ± 11%) and RegVol ≥ 45 mL (cumulative survival at 2 years: 21% ± 7% vs 24% ± 13% vs 22% ± 10%) by 3DEVM compared to those by PISA and 2DEVM, respectively. In Cox multivariable analysis, 3DEVM EROA remained independently associated with the end point (hazard ratio, 1.02, 95% CI, 1.00-1.05; P = .02). The model including EROA by 3DEVM provided significant incremental value to predict the combined end point compared to those using 2DEVM (net reclassification index = 0.51, P = .003; integrated discrimination index = 0.04, P = .014) and PISA (net reclassification index = 0.80, P < .001; integrated discrimination index = 0.06, P < .001). CONCLUSIONS: Effective regurgitant orifice area and RegVol calculated by 3DEVM were independently associated with the end point, improving the risk stratification of patients with v-SMR compared to the 2DEVM and PISA methods.

Clinical Value of a Novel Three-Dimensional Echocardiography-Derived Index of Right Ventricle-Pulmonary Artery Coupling in Tricuspid Regurgitation.

BACKGROUND: Echocardiographic surrogates of right ventricle-to-pulmonary artery (RV-PA) coupling have been reported to be associated with outcomes in patients with secondary tricuspid regurgitation (STR). However, pulmonary artery systolic pressure (PASP) is difficult to estimate using echocardiography in patients with severe STR. The aim of the present study was to evaluate the predictive power of a surrogate of RV-PA coupling obtained using right ventricular (RV) volumes measured on three-dimensional echocardiography. METHODS: One hundred eight patients (mean age, 73 ± 13 years; 61% women) with moderate or severe STR were included. RESULTS: At a median follow-up of 24 months (interquartile range, 2-48 months), 72 patients (40%) had reached the composite end point of death of any cause and heart failure hospitalization. RV-PA coupling was computed as the ratio between RV forward stroke volume (SV) (i.e., RV SV - regurgitant volume) and RV end-systolic volume (ESV). RV forward SV/ESV was significantly more related to the composite end point than RV ejection fraction (area under the curve, 0.85 [95% CI, 0.78-0.93] vs 0.73 [95% CI, 0.64-0.83], respectively; P = .03). A value of 0.40 was found to best correlate with outcome. On multivariate Cox regression, RV forward SV/ESV, tricuspid annular plane systolic excursion/PASP, and RV free wall longitudinal strain/PASP were all independently associated with the occurrence of the composite end point when added to a group of parameters including STR severity (severe vs moderate), atrial fibrillation, pulmonary arterial hypertension, right atrial volume, RV end-diastolic volume, and RV free wall longitudinal strain. RV forward SV/ESV < 0.40 (HR, 3.36; 95% CI, 1.49-7.56; P < .01) carried higher related risk than RV free wall longitudinal strain/PASP < -0.42%/mm Hg (HR, 3.1; 95% CI, 1.26-7.84; P = .01) and tricuspid annular plane systolic excursion/PASP < 0.36 mm/mm Hg (HR, 2.69; 95% CI, 1.29-5.58; P = .01). RV ejection fraction did not correlate independently with prognosis when added to the same group of variables. CONCLUSIONS: RV forward SV/ESV is associated with the risk for death and heart failure hospitalization in patients with STR.

Haemodynamic validation of the three-step HFA-PEFF algorithm to diagnose heart failure with preserved ejection fraction.

AIMS: The HFA-PEFF algorithm (Heart Failure Association-Pre-test assessment, Echocardiography and natriuretic peptide score, Functional testing in cases of uncertainty, Final aetiology) is a three-step algorithm to diagnose heart failure with preserved ejection fraction (HFpEF). It provides a three-level likelihood of HFpEF: low (score < 2), intermediate (score 2-4), or high (score > 4). HFpEF may be confirmed in individuals with a score > 4 (rule-in approach). The second step of the algorithm is based on echocardiographic features and natriuretic peptide levels. The third step implements diastolic stress echocardiography (DSE) for controversial diagnostic cases. We sought to validate the three-step HFA-PEFF algorithm against a haemodynamic diagnosis of HFpEF based on rest and exercise right heart catheterization (RHC). METHODS AND RESULTS: Seventy-three individuals with exertional dyspnoea underwent a full diagnostic work-up following the HFA-PEFF algorithm, including DSE and rest/exercise RHC. The association between the HFA-PEFF score and a haemodynamic diagnosis of HFpEF, as well as the diagnostic performance of the HFA-PEFF algorithm vs. RHC, was assessed. The diagnostic performance of left atrial (LA) strain < 24.5% and LA strain/E/E' < 3% was also assessed. The probability of HFpEF was low/intermediate/high in 8%/52%/40% of individuals at the second step of the HFA-PEFF algorithm and 8%/49%/43% at the third step. After RHC, 89% of patients were diagnosed as HFpEF and 11% as non-cardiac dyspnoea. The HFA-PEFF score resulted associated with the invasive haemodynamic diagnosis of HFpEF (P < 0.001). Sensitivity and specificity of the HFA-PEFF score for the invasive haemodynamic diagnosis of HFpEF were 45% and 100% for the second step of the algorithm and 46% and 88% for the third step of the algorithm. Neither age, sex, body mass index, obesity, chronic obstructive pulmonary disease, or paroxysmal atrial fibrillation influenced the performance of the HFA-PEFF algorithm, as these characteristics were similarly distributed over the true positive, true negative, false positive, and false negative cases. Sensitivity of the second step of the HFA-PEFF score was non-significantly improved to 60% (P = 0.08) by lowering the rule-in threshold to >3. LA strain alone had a sensitivity and specificity of 39% and 14% for haemodynamic HFpEF, increasing to 55% and 22% when corrected for E/E'. CONCLUSIONS: As compared with rest/exercise RHC, the HFA-PEFF score lacks sensitivity: Half of the patients were wrongly classified as non-cardiac dyspnoea after non-invasive tests, with a minimal impact of DSE in modifying HFpEF likelihood.

Incremental Value of Right Atrial Strain Analysis to Predict Atrial Fibrillation Recurrence After Electrical Cardioversion.

BACKGROUND: Although the assessment of left atrial (LA) mechanics has been reported to refine atrial fibrillation (AF) risk prediction, it doesn't completely predict AF recurrence. The potential added role of right atrial (RA) function in this setting is unknown. Accordingly, this study sought to evaluate the added value of RA longitudinal reservoir strain (RASr) for the prediction of AF recurrence after electrical cardioversion (ECV). METHODS: We retrospectively studied 132 consecutive patients with persistent AF who underwent elective ECV. Complete two-dimensional and speckle-tracking echocardiography analyses of LA and RA size and function were obtained in all patients before ECV. The end point was AF recurrence. RESULTS: During a 12-month follow-up, 63 patients (48%) showed AF recurrence. Both LASr and RASr were significantly lower in patients experiencing AF recurrence than in patients with persistent sinus rhythm (LASr, 10% ± 6% vs 13% ± 7%; RASr, 14% ± 10% vs 20% ± 9%, respectively; P < .001 for both). Right atrial longitudinal reservoir strain (area under the curve = 0.77; 95% CI, 0.69-0.84; P < .0001) was more strongly associated with the recurrence of AF after ECV than LASr (area under the curve = 0.69; 95% CI, 0.60-0.77; P < .0001). Kaplan-Meier curves showed that patients with both LASr ≤ 10% and RASr ≤ 15% had a significantly increased risk for AF recurrence (log-rank, P < .001). However, at multivariable Cox regression, RASr (hazard ratio, 3.26; 95% CI, 1.73-6.13; P < .001) was the only parameter independently associated with AF recurrence. Right atrial longitudinal reservoir strain was more strongly associated with the occurrence of AF relapse after ECV than LASr, and LA and RA volumes. CONCLUSION: Right atrial longitudinal reservoir strain was independently and more strongly associated than LASr with AF recurrence after elective ECV. This study highlights the importance of assessing the functional remodeling of both the RA and LA in patients with persistent AF.

Corrigendum: The atrial secondary tricuspid regurgitation is associated to more favorable outcome than the ventricular phenotype.

[This corrects the article DOI: 10.3389/fcvm.2022.1022755.].

Impact of severe secondary tricuspid regurgitation on rest and exercise hemodynamics of patients with heart failure and a preserved left ventricular ejection fraction.

Background: Both secondary tricuspid regurgitation (STR) and heart failure with preserved ejection fraction (HFpEF) are relevant public health problems in the elderly population, presenting with potential overlaps and sharing similar risk factors. However, the impact of severe STR on hemodynamics and cardiorespiratory adaptation to exercise in HFpEF remains to be clarified. Aim: To explore the impact of STR on exercise hemodynamics and cardiorespiratory adaptation in HFpEF. Methods: We analyzed invasive hemodynamics and gas-exchange data obtained at rest and during exercise from HFpEF patients with severe STR (HFpEF-STR), compared with 1:1 age-, sex-, and body mass index (BMI)- matched HFpEF patients with mild or no STR (HFpEF-controls). Results: Twelve HFpEF with atrial-STR (mean age 72 years, 92% females, BMI 28 Kg/m2) and 12 HFpEF-controls patients were analyzed. HFpEF-STR had higher (p < 0.01) right atrial pressure than HFpEF-controls both at rest (10 ± 1 vs. 5 ± 1 mmHg) and during exercise (23 ± 2 vs. 14 ± 2 mmHg). Despite higher pulmonary artery wedge pressure (PAWP) at rest in HFpEF-STR than in HFpEF-controls (17 ± 2 vs. 11 ± 2, p = 0.04), PAWP at peak exercise was no more different (28 ± 2 vs. 29 ± 2). Left ventricular transmural pressure and cardiac output (CO) increased less in HFpEF-STR than in HFpEF-controls (interaction p-value < 0.05). This latter was due to lower stroke volume (SV) values both at rest (48 ± 9 vs. 77 ± 9 mL, p < 0.05) and at peak exercise (54 ± 10 vs. 93 ± 10 mL, p < 0.05). Despite these differences, the two groups of patients laid on the same oxygen consumption isophlets because of the increased peripheral oxygen extraction in HFpEF-STR (p < 0.01). We found an inverse relationship between pulmonary vascular resistance and SV, both at rest and at peak exercise (R 2 = 0.12 and 0.19, respectively). Conclusions: Severe STR complicating HFpEF impairs SV and CO reserve, leading to pulmonary vascular de-recruitment and relative left heart underfilling, undermining the typical HFpEF pathophysiology.

Effects of cardiac rehabilitation on cardiopulmonary test parameters in heart failure: A real world experience.

Background: Cardio-Pulmonary Exercise Test (CPET) is the gold standard for evaluation of patients with heart failure (HF); however, its use is limited in everyday practice. We analyzed the use of CPET for HF management in the real world. Methods: From 2009 to 2022, 341 patients with HF underwent 12-16 weeks of rehabilitation in our Centre. We present data from 203 patients (60%), excluding those unable to perform CPET, those with anaemia and severe pulmonary disease. Before and after rehabilitation, we performed CPET, blood tests and echocardiography, tailoring individual physical training to the results of baseline test. The following variables were considered: peak Respiratory Equivalent Ratio (RER), peakVO2 (ml/Kg/min), VO2 at aerobic threshold (VO2AT,% maximal), VE/VCO2 slope, P(ET)CO2, VO2 /Work ratio (ΔVO2/ΔWork). Results: Rehabilitation improved peak VO2, pulse O2, VO2 AT and ΔVO2/ΔWork in all patients by about 13% (p < 0.01). Most patients (126, 62%) showed a reduced left ventricular ejection fraction (HFrEF), but rehabilitation was effective also in patients with mildly reduced (HFmrEF: n = 55, 27%) or preserved ejection fraction (HFpEF: n = 22, 11%). Conclusions: Rehabilitation in patients with heart failure induces a significant recovery of cardiorespiratory performance easily assessed by CPET, that is applicable to the majority of them and should be used routinely in the programming and evaluating of cardiac rehabilitation programs.