Cardiopulmonary Management for Severe Aortic Valve Stenosis With Noninvasive Ventilation Using a Nasopharyngeal Tube.

The nasopharyngeal tube (NT) is an effective interface for noninvasive ventilation (NIV). In cases of severe heart failure, assistance with noninvasive positive-pressure ventilation (NPPV) effectively reduces afterload and alleviates respiratory effort. We present the case of a three-day-old male neonate diagnosed with severe aortic valve stenosis (AS). In respiratory management, extubation was delayed due to increased respiratory effort and afterload, so this patient was extubated and managed with NPPV using an NT. An uncuffed endotracheal tube was inserted, initiating NIV with a positive end-expiratory pressure of 8 cmH2O. The patient exhibited stable vital signs post-extubation and was weaned off NPPV and transferred to the general ward. In this case of severe AS, the use of NT as an interface for NPPV demonstrated efficacy in respiratory and circulatory management. This approach could have shortened the duration of mechanical ventilation and facilitated safe postoperative care, highlighting the potential benefits of NT in managing severe heart failure.

Comparison of Pressure vs Volume Overload Ventricular Wall Stress in Patients With Valvular Heart Disease.

BACKGROUND: Aortic stenosis (AS) and mitral regurgitation (MR) result in different patterns of left ventricular remodeling and hypertrophy. OBJECTIVES: We characterized left ventricular wall stress (LVWS) profiles in pressure and volume-overloaded systems, examined the relationship between baseline LVWS and cardiac remodeling, and assessed the acute effects of valve intervention on LVWS using invasive pressures combined with cardiac magnetic resonance (CMR) imaging measures of left ventricular volumes/mass. METHODS: A total of 47 patients with severe AS undergoing transcatheter aortic valve replacement (TAVR) and 15 patients with severe MR undergoing MitraClip (MC) underwent a 6-minute walk test (6MWT), transthoracic echocardiogram, and CMR before their procedures. Catheters in the left ventricle were used to record hemodynamic changes before and after valve/clip deployment. This was integrated with CMR data to calculate LVWS before and after intervention. RESULTS: The TAVR group demonstrated significant reductions in systolic LVWS post procedure (median 24.7 Pa [IQR: 14 Pa] pre vs median 17.3 Pa [IQR: 12 Pa] post; P < 0.001). The MC group demonstrated significant reductions in diastolic LVWS (median 6.4 Pa [IQR: 5 Pa] pre vs median 4.3 Pa [IQR: 4.1 Pa] post; P = 0.021) with no significant change in systolic LVWS (30.6 ±1.61 pre vs 33 ±2.47 Pa post; P = 0.16). There was an inverse correlation between baseline systolic LVWS and 6MWT in the TAVR group (r = -0.31; P = 0.04). CONCLUSIONS: TAVR results in significant reductions in systolic LVWS acutely. MC results in significant reductions in diastolic LVWS. Higher baseline systolic LVWS in TAVR is associated with shorter 6MWT suggesting that in AS, LVWS may be a useful marker of early decompensation.

Right Ventricular Pressure Waveform Analysis-Clinical Relevance and Future Directions.

Continuous measurement of pressure in the right atrium and pulmonary artery has commonly been used to monitor right ventricular function in critically ill and surgical patients. This approach is largely based upon the assumption that right atrial and pulmonary arterial pressures provide accurate surrogates for diastolic filling and peak right ventricular pressures, respectively. However, due to both technical and physiologic factors, this assumption is not always true. Accordingly, recent studies have begun to emphasize the potential clinical value of also measuring right ventricular pressure at the bedside. This has highlighted both past and emerging research demonstrating the utility of analyzing not only the amplitude of right ventricular pressure but also the shape of the pressure waveform. This brief review summarizes data demonstrating that combining conventional measurements of right ventricular pressure with variables derived from waveform shape allows for more comprehensive and ideally continuous bedside assessment of right ventricular function, particularly when combined with stroke volume measurement or 3D echocardiography, and discusses the potential use of right ventricular pressure analysis in computational models for evaluating cardiac function.

Association of velocity-pressure loop-derived values recorded during neurosurgical procedures with postoperative organ failure biomarkers: a retrospective single-center study.

BACKGROUND: Perioperative renal and myocardial protection primarily depends on preoperative prediction tools, along with intraoperative optimization of cardiac output (CO) and mean arterial pressure (MAP). We hypothesise that monitoring the intraoperative global afterload angle (GALA), a proxy of ventricular afterload derived from the velocity pressure (VP) loop, could better predict changes in postoperative biomarkers than the recommended traditional MAP and CO. METHOD: This retrospective monocentric study included patients programmed for neurosurgery with continuous VP loop monitoring. Patients with hemodynamic instability were excluded. Those presenting a 1-day post-surgery increase in creatinine, B-type natriuretic peptide, or troponin Ic us were labelled Bio+, Bio- otherwise. Demographics, intra-operative data, and comorbidities were considered as covariates. The study aimed to determine if intraoperative GALA monitoring could predict early postoperative biomarker disruption. RESULT: From November 2018 to November 2020, 86 patients were analysed (Bio+/Bio- = 47/39). Bio+ patients were significantly older (62 [54-69] vs. 42 [34-57] years, p < 0.0001), More often hypertensive (25% vs. 9%, p = 0.009), and more frequently treated with antihypertensive drugs (31.9% vs. 7.7%, p = 0.013). GALA was significantly larger in Bio+ patients (40 [31-56] vs. 23 [19-29] °, p < 0.0001), while CO, MAP, and cumulative time spent <65mmHg were similar between groups. GALA exhibited strong predictive performances for postoperative biological deterioration (AUC = 0.88 [0.80-0.95]), significantly outperforming MAP (MAP AUC = 0.55 [0.43-0.68], p < 0.0001). CONCLUSION: GALA under general anaesthesia prove more effective in detecting patients at risk of early cardiac or renal biological deterioration, compared to classical hemodynamic parameters.

Right Ventricular and Right Atrial Strain Are Associated with Kidney Dysfunction in Acute Heart Failure.

BACKGROUND: In acute heart failure (HF), low cardiac output and venous congestion are pathophysiological mechanisms that contribute to renal function impairment. This study investigated the association between advanced echocardiographic measures of right ventricular and atrial function and renal impairment in patients with acute HF. METHODS AND RESULTS: A total of 377 patients hospitalized for acute HF were prospectively evaluated. Estimated glomerular filtration rate (eGFR) on admission was measured using the 2021 Chronic Kidney Disease Epidemiology Collaboration creatinine equation. Advanced echocardiographic assessment was performed on admission. Patients with eGFR < 45 mL/min/1.73 m2 were more likely to have chronic heart failure, chronic atrial fibrillation, and type 2 diabetes mellitus compared to patients with eGFR ≥ 45 mL/min/1.73 m2. Patients with lower eGFR had lower cardiac output, higher mean E/e' ratio, larger right ventricular (RV) size, worse RV free wall longitudinal strain, more impaired right atrial (RA) reservoir strain, and more frequent severe tricuspid regurgitation. RV free wall longitudinal strain and RA reservoir strain were the only independent echocardiographic associates of low eGFR, whereas cardiac output was not. CONCLUSIONS: Impaired RV and RA longitudinal strain were independently associated with eGFR < 45 mL/min/1.73 m2 in acute HF, while reduced cardiac output was not. This suggests that RV and RA dysfunction underlying venous congestion and increased renal afterload are more important pathophysiological determinants of renal impairment in acute HF than reduced cardiac output.

The Effect of Positive End-Expiratory Pressure on Pulmonary Vascular Resistance Depends on Lung Recruitability in Patients with Acute Respiratory Distress Syndrome.

Rationale: A U-shaped relationship should exist between lung volume and pulmonary vascular resistance (PVR), with minimal PVR at FRC. Thus, positive end-expiratory pressure (PEEP) in patients with acute respiratory distress syndrome (ARDS) should increase PVR if it induces significant lung distension compared with recruitment. However, this has never been proved in patients. Objectives: To study the effects of PEEP on PVR according to lung recruitability, evaluated by the recruitment-to-inflation (R/I) ratio. Methods: In patients with ARDS, we measured hemodynamic (pulmonary artery catheter), echocardiographic, and ventilatory variables (including esophageal pressure) at both low PEEP and higher PEEP by 10 cm H2O. Preload responsiveness was assessed by the passive leg-raising test at high PEEP. Measurements and Main Results: We enrolled 23 patients, including 10 low recruiters (R/I <0.5) and 13 high recruiters (R/I ⩾0.5). Raising PEEP from 4 (2-5) to 14 (12-15) cm H2O increased PVR in low recruiters (from 160 [120-297] to 243 [166-380] dyn·s/cm5; P < 0.01), whereas PVR was unchanged in high recruiters (from 224 [185-289] to 235 [168-300] dyn·s/cm5; P = 0.55). Right-to-left ventricular end-diastolic area ratio simultaneously increased in low recruiters (from 0.54 [0.50-0.59] to 0.64 [0.56-0.70]; P < 0.01) while remaining stable in high recruiters (from 0.70 [0.65-0.79] to 0.68 [0.58-0.80]; P = 0.48). Raising PEEP decreased cardiac index only in preload responsive patients. Conclusions: PEEP increases PVR only when it induces significant lung distension compared with recruitment according to the R/I ratio. Tailoring PEEP on this recruitability index should mitigate its hemodynamic effects.

Prognostic value of the echocardiographic ratio tricuspid annular plane systolic excursion / pulmonary arterial systolic pressure in acute pulmonary embolism.

INTRODUCTION: The occurrence of death from acute pulmonary embolism (PE) is often linked to right ventricular (RV) failure, arising from an imbalance between RV systolic function and heightened RV afterload. In our study, we posited that an echocardiographic ratio derived from this disparity [RV systolic function assessed by tricuspid annular plane systolic excursion (TAPSE) divided by pulmonary arterial systolic pressure (PASP)] could offer superior predictive value for adverse outcomes compared to individual measurements of TAPSE and PASP alone. METHODS: We conducted a retrospective analysis using data from a University Hospital Centre spanning from 2017 to 2023. All individuals with confirmed PE and a formal transthoracic echocardiogram within 7 days of diagnosis were included. The primary endpoint was a composite outcome of death, hemodynamic deterioration needing introduction of inotropes or thrombolysis within 30 days. Secondary endpoints included 6 months all-cause mortality and onset of right-sided heart failure. RESULTS: Thirty-eight patients were included. Mean age was 58 ±15 years old. A male predominance was noted: 23 male patients (60.5%) and 15 female patients (39.5%). Eight patients met the primary composite endpoint while nine patients met the secondary composite endpoint. In multivariate analysis, the TAPSE/PASP ratio was independently associated with the primary outcome (OR=2.77, 95% CI 1.101-10.23, P=0.042). A TAPSE/PASP ratio <0.3 was independently associated with the secondary outcome (OR=3.07, 95% CI 1.185-10.18, P=0.034). CONCLUSION: This study suggests that a combined echocardiographic ratio of RV function to afterload is effective in predicting adverse outcomes in acute PE.

Immediate cardiopulmonary responses to consecutive pulmonary embolism: a randomized, controlled, experimental study.

BACKGROUND: Acute pulmonary embolism (PE) induces ventilation-perfusion mismatch and hypoxia and increases pulmonary pressure and right ventricular (RV) afterload, entailing potentially fatal RV failure within a short timeframe. Cardiopulmonary factors may respond differently to increased clot burden. We aimed to elucidate immediate cardiopulmonary responses during successive PE episodes in a porcine model. METHODS: This was a randomized, controlled, blinded study of repeated measurements. Twelve pigs were randomly assigned to receive sham procedures or consecutive PEs every 15 min until doubling of mean pulmonary pressure. Cardiopulmonary assessments were conducted at 1, 2, 5, and 13 min after each PE using pressure-volume loops, invasive pressures, and arterial and mixed venous blood gas analyses. ANOVA and mixed-model statistical analyses were applied. RESULTS: Pulmonary pressures increased after the initial PE administration (p < 0.0001), with a higher pulmonary pressure change compared to pressure change observed after the following PEs. Conversely, RV arterial elastance and pulmonary vascular resistance was not increased after the first PE, but after three PEs an increase was observed (p = 0.0103 and p = 0.0015, respectively). RV dilatation occurred following initial PEs, while RV ejection fraction declined after the third PE (p = 0.004). RV coupling exhibited a decreasing trend from the first PE (p = 0.095), despite increased mechanical work (p = 0.003). Ventilatory variables displayed more incremental changes with successive PEs. CONCLUSION: In an experimental model of consecutive PE, RV afterload elevation and dysfunction manifested after the third PE, in contrast to pulmonary pressure that increased after the first PE. Ventilatory variables exhibited a more direct association with clot burden.

Prognostic Value of Right Ventricular Afterload in Patients Undergoing Mitral Transcatheter Edge-to-Edge Repair.

BACKGROUND: Pulmonary hypertension (PH) and secondary mitral regurgitation (MR) are associated with adverse outcomes after mitral transcatheter edge-to-edge repair. We aim to study the prognostic value of invasively measured right ventricular afterload in patients undergoing mitral transcatheter edge-to-edge repair. METHODS AND RESULTS: We identified patients who underwent right heart catheterization ≤1 month before transcatheter edge-to-edge repair. The end points were all-cause mortality and a composite of mortality and heart failure hospitalization at 2 years. Using the receiver operating characteristic curve-derived threshold of 0.6 for pulmonary effective arterial elastance ([Ea], pulmonary artery systolic pressure/stroke volume), patients were stratified into 3 profiles based on PH severity (low elastance [HE]: Ea <0.6/mean pulmonary artery pressure (mPAP)) <35; High Elastance with No/Mild PH (HE-): Ea ≥0.6/mPAP <35; and HE with Moderate/Severe PH (HE+): Ea ≥0.6/mPAP ≥35) and MR pathogenesis (Primary MR [PMR])/low elastance, PMR/HE, and secondary MR). The association between this classification and clinical outcomes was examined using Cox regression. Among 114 patients included, 50.9% had PMR. Mean±SD age was 74.7±10.6 years. Patients with Ea ≥0.6 were more likely to have diabetes, atrial fibrillation, New York Heart Association III/IV status, and secondary MR (all P<0.05). Overall, 2-year cumulative survival was 71.1% and was lower in patients with secondary MR and mPAP ≥35. Compared with patients with low elastance, cumulative 2-year event-free survival was significantly lower in HE- and HE+ patients (85.5% versus 50.4% versus 41.0%, respectively, P=0.001). Also, cumulative 2-year event-free survival was significantly higher in patients with PMR/low elastance when compared with PMR/HE and patients with secondary mitral regurgitation (85.5% versus 55.5% versus 46.1%, respectively, P=0.005). CONCLUSIONS: Assessment of the preprocedural cardiopulmonary profile based on mPAP, MR pathogenesis, and Ea guides patient selection by identifying hemodynamic features that indicate likely benefit from mitral-transcatheter edge-to-edge repair in PH or lack thereof.

Ex Vivo Working Porcine Heart Model.

Ex vivo working porcine heart models allow for the study of a heart's function and physiology outside the living organism. These models are particularly useful due to the anatomical and physiological similarities between porcine and human hearts, providing an experimental platform to investigate cardiac disease or assess donor heart viability for transplantation. This chapter presents an in-depth discussion of the model's components, including the perfusate, preload, and afterload. We explore the challenges of emulating cardiac afterload and present a historical perspective on afterload modeling, discussing various methodologies and their respective limitations. An actively controlled afterload device is introduced to enhance the model's ability to rapidly adjust pressure in the large arteries, thereby providing a more accurate and dynamic experimental model. Finally, we provide a comprehensive experimental protocol for the ex vivo working porcine heart model.

Increased aortic pressures and pulsatile afterload components promote concentric left ventricular remodeling in adults with transposition of the great arteries and arterial switch operation.

BACKGROUND: Functional abnormalities of the ascending aorta (AA) have been mainly reported in young patients who underwent arterial switch operation (ASO) for transposition of the great arteries (TGA). OBJECTIVES: To compare systolic, diastolic brachial and central blood pressures (bSBP, bDBP, cSBP, cDBP), aortic biomechanical parameters, and left ventricular (LV) afterload criteria in adult ASO patients with healthy controls and to assess their relationships with LV remodeling and aortic size. MATERIALS AND METHODS: Forty-one prospectively enrolled patients (16.8 to 35.8 years) and 41 age- and sex-matched healthy volunteers underwent cardiac MRI to assess LV remodeling with simultaneous brachial BP estimation. After MRI, carotid-femoral tonometry was performed to measure pulse wave velocity (cfPWV), cSBP and cDBP for further calculation of pulse pressure (cPP), AA distensibility (AAD), and AA and LV elastance (AAE, LVE). RESULTS: bSBP, bDBP, cSBP,cDBP and cPP were all significantly higher in ASO group than in controls: cSBP (116.5 ± 13.8 vs 106.1 ± 12.0, p < 0.001), cDBP (72.5 ± 6.9 vs 67.1 ± 9.4, p = 0.002), cPP (44.0 ± 12.1 vs 39.1 ± 8.9, p = 0.003) and not related to aortic size. AAD were decreased in ASO patients vs controls (4.70 ± 2.72 vs 6.69 ± 2.16, p < 0.001). LV mass was correlated with bSBP, cSBP, cPP (ρ = 0.48; p < 0.001), while concentric LV remodeling was correlated with AAE (ρ = 0.60, p < 0.001) and LVE (ρ = 0.32, p = 0.04), but not with distensibility. CONCLUSION: Even without reaching arterial hypertension, aortic sBP and PP are increased in the adult TGA population after ASO, altering the pulsatile components of afterload and contributing to LV concentric remodeling.

Efficacy and safety of the Aria pulmonary endovascular device in pulmonary hypertension.

AIMS: A common feature of various forms of pulmonary hypertension (PH) is progressive decline of pulmonary arterial compliance (CPA), which correlates with reduced survival. In this acute study, we evaluated feasibility, safety and haemodynamic performance of the Aria pulmonary endovascular device in patients with PH associated with left heart disease (PH-LHD) and chronic lung disease (PH-CLD). METHODS AND RESULTS: Eight patients with PH-LHD and 10 patients with PH-CLD were included in this study. The device was placed in the main pulmonary artery via the right femoral vein and was connected by a catheter to a gas-filled reservoir outside the body. During systole, gas shifts from the balloon to the reservoir, leading to deflation of the balloon. In diastole, the gas returns from the reservoir to the balloon, leading to balloon inflation and enhancing diastolic blood flow to the distal pulmonary capillary bed. Haemodynamics were assessed at baseline, and again with device off, device on and device off. The primary safety endpoint was the incidence of serious adverse events through 30 days after the procedure. No complications or investigational device-related serious adverse events occurred. Device activation in PH-LHD and PH-CLD patients decreased pulmonary arterial pulse pressure by 5.6 ± 4.2 mmHg (-12%; p = 0.003) and 4.2 ± 2.2 mmHg (-11%; p < 0.001), increased CPA by 0.4 ± 0.2 ml/mmHg (+23%; p = 0.004) and 0.4 ± 0.3 ml/mmHg (+25%; p = 0.001), and increased right ventricular-to-pulmonary vascular (RV-PV) coupling by 0.24 ± 0.18 (+40%; p = 0.012) and 0.11 ± 0.07 (+21%; p = 0.001), respectively. CONCLUSIONS: Temporary implantation of the Aria endovascular device was feasible and safe. Device activation resulted in acute improvement of CPA and RV-PV coupling.

[Septic cardiomyopathy-diagnosis and estimation of disease severity]. / Septische Kardiomyopathie ­ Diagnostik und Schweregradabschätzung.

BACKGROUND: The relevance of septic cardiomyopathy is frequently underestimated due to the complexity of the pattern of cardiac injury and the corresponding difficulties in quantifying the degree of functional impairment. AIM: Account of the methods for diagnosis and severity classification of septic cardiomyopathy. METHODS: Literature review and analysis of the main findings. RESULTS: Septic cardiomyopathy is characterized by both systolic and diastolic impairment of not only the left, but also the right ventricle, as well as by sinus-tachycardiomyopathy (≥ 90-95 beats/min) of variable degree. Sepsis-related organ failure assessment (SOFA) score, left ventricular ejection fraction (LVEF), ECG and cardiac biomarkers do not help in grading severity of septic cardiomyopathy. For that purpose either a sophisticated echocardiography diagnosis is mandatory, or the measurement of those global heart function parameters which take into account the dependency of cardiac output on afterload, in view of the pronounced vasodilatation in sepsis and septic shock, is needed. A suitable parameter on the basis of cardiac output measurement is afterload-related cardiac performance (ACP), which gives the percentage of cardiac output in a septic patient related to the cardiac output a healthy heart pumps when challenged by a fall in systemic vascular resistance to the same extent. The calculation of ACP shows that at least one in two septic patients suffers from impaired heart function and that mortality increases as severity increases. CONCLUSION: Simple parameters like LVEF are not apt for diagnosis nor for disease severity classification of septic cardiomyopathy. For that purpose either sophisticated echocardiography techniques or load-independent parameters-best validated-ACP measurements are appropriate.

Multimodality imaging for the global evaluation of aortic stenosis: The valve, the ventricle, the afterload.

Aortic stenosis (AS) is the most common valvular heart disease growing in parallel to the increment of life expectancy. Besides the valve, the degenerative process affects the aorta, impairing its elastic properties and leading to increased systemic resistance. The composite of valvular and systemic afterload mediates ventricular damage. The first step of a thorough evaluation of AS should include a detailed assessment of valvular anatomy and hemodynamics. Subsequently, the ventricle, and the global afterload should be assessed to define disease stage and prognosis. Multimodality imaging is of paramount importance for the comprehensive evaluation of these three elements. Echocardiography is the cornerstone modality whereas Multi-Detector Computed Tomography and Cardiac Magnetic Resonance provide useful complementary information. This review comprehensively examines the merits of these imaging modalities in AS for the evaluation of the valve, the ventricle, and the afterload and ultimately endeavors to integrate them in a holistic assessment of AS.

Exercise and pulsatile pulmonary vascular loading in chronic thromboembolic pulmonary disease.

Chronic thromboembolic pulmonary disease (CTEPD) is characterized by organized nonresolving thrombi in pulmonary arteries (PA). In CTEPD with pulmonary hypertension (PH), chronic thromboembolic PH (CTEPH), early wave reflection results in abnormalities of pulsatile afterload and augmented PA pressures. We hypothesized that exercise during right heart catheterization (RHC) would elicit more frequent elevations of pulsatile vascular afterload than resistive elevations in patients with CTEPD without PH. The interdependent physiology of pulmonary venous and PA hemodynamics was also evaluated. Consecutive patients with CTEPD without PH (resting mean PA pressure ≤20 mmHg) undergoing an exercise RHC were identified. Latent resistive and pulsatile abnormalities of pulmonary vascular afterload were defined as an exercise mean PA pressure/cardiac output >3 WU, and PA pulse pressure to PA wedge pressure (PA PP/PAWP) ratio >2.5, respectively. Forty-five patients (29% female, 53 ± 14 years) with CTEPD without PH were analyzed. With exercise, 19 patients had no abnormalities (ExNOR), 26 patients had abnormalities (ExABN) of pulsatile (20), resistive (2), or both (4) elements of pulmonary vascular afterload. Exercise elicited elevations of pulsatile afterload (53%) more commonly than resistive afterload (13%) (p < 0.001). ExABN patients had lower PA compliance and higher pulmonary vascular resistance at rest and exercise and prolonged resistance-compliance time product at rest. The physiological relationship between changes in PA pressures relative to PAWP was disrupted in the ExABN group. In CTEPD without PH, exercise RHC revealed latent pulmonary vascular afterload elevations in 58% of patients with more frequent augmentation of pulsatile than resistive pulmonary vascular afterload.

Ascending aortic impedance in young endurance athletes: a time-resolved phase-contrast MRI study.

Ventricular-vascular coupling in endurance athletes remains incompletely understood. The purpose of this study was to determine the ascending aortic impedance in endurance athletes and explore its associations with traditional cardiovascular measurements. In 15 young male endurance runners and 19 young healthy men, time-resolved (CINE) two-dimensional (2-D) phase-contrast MRI quantified the ascending aortic flow while the pressure waveform was simultaneously collected via a generalized transfer function. The aortic impedance modulus and phase were calculated in the frequency domain while characteristic impedance (ZcF) was calculated by averaging moduli between the 4th and 8th heart rate (HR) harmonics. Stroke volume (SV), left ventricular (LV) morphometry, double product, aortic compliance, and total peripheral resistance (TPR) were also measured. Endurance athletes had higher SV, slower HR, greater LV end-diastolic volume and mass, and lower double product than sedentary participants (all P < 0.05). ZcF was significantly lower in athletes than in sedentary participants (73.3 ± 19.2 vs. 93.4 ± 19.0 dyn·s/cm5, P = 0.005). Furthermore, ZcF was negatively correlated with SV (r = -0.691) and aortic compliance (r = -0.601) but was positively correlated with double product (r = 0.445) and TPR (r = 0.458; all P < 0.05). Multivariate analysis revealed that ZcF was the strongest predictor of SV followed by TPR and HR (adjusted R2 = 0.788, P < 0.001). Therefore, our findings collectively suggest that LV afterload quantified by aortic ZcF is significantly lower in endurance athletes than in sedentary adults. The lower pulsatile LV afterload may contribute to greater SV in endurance athletes.NEW & NOTEWORTHY This is the first study to investigate aortic impedance with the noninvasive, simultaneous recordings of aortic pressure using SphygmoCor XCEL and flow using phase-contrast MRI. We found that the characteristic impedance (Zc) is significantly lower in endurance athletes than sedentary adults, is the strongest predictor of stroke volume (SV), and is inversely associated with aortic compliance. These findings suggest that aortic impedance is a key determinant of the ventricular-vascular coupling adapted to long-term training in endurance athletes.

Can the hemodynamic model in heart failure be restored based on analysis of ventricular-arterial coupling?

The hemodynamic model was inappropriate to explain the disappointing effect of vasodilation and the beneficial effect of beta-blockade in chronic heart failure. A more nuanced hemodynamic analysis, taking both steady and pulsatile hemodynamics into consideration, improves insight into these apparently enigmatic effects. Of particular interest is the velocity of early systolic flow as a determinant of left ventricular afterload. Several drugs, in particular beta-blockers, directly or indirectly, influence the velocity of early systolic flow. Thus, the hemodynamic model in heart failure may deserve reconsideration.

Determinants and prognostic implications of left atrial reverse remodelling after coarctation of aorta repair in adults.

AIMS: Left atrial (LA) dysfunction and atrial fibrillation are also relatively common in adults with coarctation of aorta (COA), and the severity of LA dysfunction is associated with a higher risk of atrial fibrillation in this population. The purpose of this study was to determine whether LA function improved after COA repair (LA reverse remodelling), and the relationship between LA reverse remodelling and atrial fibrillation. METHODS AND RESULTS: Retrospective cohort study of adults undergoing COA repair (2003-20). LA reservoir strain was assessed pre intervention and 12-24 months post intervention, using speckle tracking echocardiography. Incident atrial fibrillation was assessed from COA repair to last follow-up. Of 261 adults who underwent COA repair [age 37 ± 13 years; males 148 (57%)], 124 (47%) and 137 (53%) presented with native vs. recurrent COA, respectively. Of 261 patients, 231 (82%) and 48 (18%) underwent surgical and transcatheter COA repair, respectively. The LA reservoir strain increased from 32 ± 8% (pre intervention) to 39 ± 7% (post intervention), yielding a relative increase of 21 ± 5%. Older age [ß ± standard error (SE) -0.16 ± 0.09 per 5 years, P = 0.02], higher systolic blood pressure (ß ± SE -0.12 ± 0.04 per 5 mmHg, P = 0.005), and higher residual COA mean gradient (ß ± SE -0.17 ± 0.06 per 5 mmHg, P = 0.002) post intervention were associated with less LA reverse remodelling, after adjustment for sex, hypertension diagnosis, and left ventricular indices. LA reverse remodelling (hazard ratio 0.97, 95% confidence interval 0.96-0.98 per 1% increase from pre-intervention LA function, P = 0.006) was associated with a lower risk of atrial fibrillation after adjustment for age, sex, pre-intervention LA reservoir strain, and history of atrial fibrillation. CONCLUSION: COA repair resulted in improved LA function and decreased risk for atrial fibrillation, especially in patients without residual hypertension or significant residual COA gradient.