Left Pressure Research Articles

Hemodynamic Optimization by Invasive Ramp Test in Patients Supported With HeartMate 3 Left Ventricular Assist Device.

In patients supported by the HeartMate 3 left ventricular assist device (HM3 LVAD), pump speed adjustments may improve hemodynamics. We investigated the hemodynamic implications of speed adjustments in HM3 recipients undergoing hemodynamic ramp tests. Clinically stable HM3 recipients who underwent routine invasive hemodynamic ramp tests between 2015 and 2022 at our center were included. Filling pressure optimization, defined as central venous pressure (CVP) <12 mm Hg and pulmonary capillary wedge pressure (PCWP) <18 mm Hg, was assessed at baseline and final pump speeds. Patients with optimized pressures were compared to nonoptimized patients. Overall 60 HM3 recipients with a median age of 62 years (56, 71) and time from LVAD implantation of 187 days (124, 476) were included. Optimized filling pressures were found in 35 patients (58%) at baseline speed. Speed was adjusted in 84% of the nonoptimized patients. Consequently, 39 patients (65%) had optimized pressures at final speed. There were no significant differences in hemodynamic findings between baseline and final speeds ( p > 0.05 for all). Six and 12 month readmission-free rates were higher in optimized compared with nonoptimized patients ( p = 0.03 for both), predominantly due to lower cardiac readmission-free rates ( p = 0.052). In stable outpatients supported with HM3 who underwent routine ramp tests, optimized hemodynamics were achieved in only 2 of 3 of the patients. Patients with optimized pressures had lower all-cause readmission rates, primarily driven by fewer cardiac-related hospitalizations.

Association of transcatheter left atrial appendage occlusion with acute changes in left atrial pressure: An invasive hemodynamic study

BackgroundThe hemodynamic effects of transcatheter left atrial appendage occlusion (LAAO) remain unclear. ObjectiveWe sought to assess the effect of LAAO on invasive hemodynamics and their correlation with clinical outcomes. MethodsWe recorded mean left atrial pressure (mLAP) before and after device deployment. We assessed the prevalence and predictors of mLAP increase after deployment, the association between significant mLAP increase after deployment and 45-day peridevice leak (PDL), and the association between mLAP increase and heart failure (HF) hospitalization. A significant mLAP increase was defined as one equal to or greater than the mean percentage increase in mLAP after deployment (≥28%). ResultsWe included 302 patients (36.4% female; mean age, 75.8 ± 9.5 years). After deployment, mLAP increased in 48% of patients, 38% of whom experienced significant mLAP increase. Independent predictors of mLAP increase were baseline mLAP ≤14 mm Hg, nonparoxysmal atrial fibrillation, and age per 5 years (odds ratios: 3.66 [95% CI, 2.21–6.05], 1.81 [95% CI, 1.08–3.02], and 0.85 [95% CI, 0.73–0.99], respectively). Significant mLAP increase was an independent predictor of 45-day PDL (odds ratio, 2.55; 95% CI, 1.04–6.26). There was no association between mLAP increase and HF hospitalization. ConclusionAfter deployment, mLAP acutely rises in 48% of patients, although this is not associated with increased HF hospitalizations. PDL is more likely to develop at 45 days in patients with significant increase in mLAP after deployment, although most leaks were small (<5 mm). These findings suggest that mLAP increase after deployment is not associated with major safety concerns. Additional studies are warranted to explore the long-term hemodynamic effects of LAAO.

Noninvasive Prediction of Pulmonary Capillary Wedge Pressure in Patients With Normal Left Ventricular Ejection Fraction: Comparison of Cardiac Magnetic Resonance With Comprehensive Echocardiography

Cardiac magnetic resonance (CMR) was recently reported to predict mean pulmonary capillary wedge pressure (PCWP). However, there is a paucity of data on its accuracy for estimation of PCWP in patients with normal left ventricular (LV) ejection fraction (EF). We sought to examine its accuracy against the invasive gold standard and to compare it with the accuracy of comprehensive echocardiography. Stable patients with EF of ≥50% who underwent right heart catheterization, CMR, and echocardiographic imaging within 1week were included. Pulmonary capillary wedge pressure was estimated by CMR using a previously validated equation where PCWP is estimated based on the left atrial maximum volume and LV mass. Echocardiographic estimation of PCWP was based on 2016 American Society of Echocardiography/European Association of Cardiovascular Imaging guidelines, taking into account the presence of myocardial disease. The mean age of the 79 patients was 55±15years, and 58.2% were female. There were 33 patients with PCWP >15mm Hg by right heart catheterization. Cardiac magnetic resonance prediction of PCWP had an area under the curve (AUC)=0.72. In comparison, echocardiographic prediction of PCWP showed a higher accuracy (AUC=0.87 vs AUC=0.72; P=.008). In patients with normal LV EF, CMR estimation of mean PCWP based on LV mass and left atrial volume has modest accuracy for detecting patients with mean PCWP >15mm Hg. Comprehensive echocardiography predicts elevated PCWP with higher accuracy in comparison with CMR.

Left ventricular to left arial volume ratio in the assessment of filling pressure in patients with dyspnoea and preserved ejection fraction.

Assessing filling pressure (FP) remains a clinical challenge despite advancements in non-invasive imaging techniques. This study investigates the utility of echocardiographic left ventricular (LV) to left atrial (LA) volume ratio in estimating the resting FP in patients with dyspnoea and preserved ejection fraction (EF). This study is a prospective, single-centre analysis of 53 consecutive patients with dyspnoea (New York Heart Association grade 2 or 3) and LVEF of ≥50% (mean age 71 ± 10 years) who underwent cardiac catheterisation, including direct measurement of LA pressure at rest using retrograde technique. Echocardiographic data were obtained 1.5 ± 1.0 h after cardiac catheterisation. The patients were divided into two groups: Group 1 consisted of individuals with elevated FP, indicated by a mean LA pressure or mean pulmonary capillary wedge pressure of >12 mmHg, and Group 2 comprised of patients with normal FP. The LV and LA volumes were measured at three specific points: the minimum volume (LVES, LAmin), the volume during diastasis (LVdias, LAdias), and the maximum volume (LVED, LAmax). The corresponding LV/LA volume ratios were analysed: end-systole (LVES/LAmax), diastasis (LVdias/LAdias), and end-diastole (LVED/LAmin). The patients in Group 1 exhibited lower LV/LA volume ratios compared with those in Group 2 (LVES/LAmax 0.44 ± 0.12 vs. 0.60 ± 0.23, P = 0.0032; LVdias/LAdias 1.13 ± 0.30 vs. 1.56 ± 0.49, P = 0.0007; LVED/LAmin 2.71 ± 1.57 vs. 4.44 ± 1.70, P = 0.0004). The LV/LA volume ratios correlated inversely with an increased FP (LVES/LAmax, r = -0.40, P = 0.0033; LVdias/LAdias, r = -0.45, P = 0.0007; LVED/LAmin, r = -0.55, P < 0.0001). Among all the measurements, the LVdias/LAdias ratio demonstrated the highest discriminatory power to distinguish patients with elevated FP from normal FP, with a cut-off value of ≤1.24 [area under the curve (AUC) = 0.822] for the entire group, encompassing both sinus rhythm and atrial fibrillation. For patients in sinus rhythm specifically, the cut-off value was ≤1.28 (AUC = 0.799), with P < 0.0001 for both. The LVdias/LAdias index demonstrated non-inferiority to the E/e' ratio [ΔAUC = 0.159, confidence interval (CI) = -0.020-0.338; P = 0.0809], while surpassing the indices of LA reservoir function (ΔAUC = 0.249, CI = 0.044-0.454; P = 0.0176), LA reservoir strain (ΔAUC = 0.333, CI = 0.149-0.517; P = 0.0004), and LAmax index (ΔAUC = 0.224, CI = 0.043-0.406; P = 0.0152) in diagnosing patients with elevated FP. The study presents a straightforward and reproducible method for non-invasive estimation of FP using routine TTE in patients with dyspnoea and preserved EF. The LVdias/LAdias index emerges as a promising indicator for identifying elevated FP, demonstrating comparable or even superior performance to established parameters.

The Impact of Diabetes on Haemodynamic and Cardiometabolic Responses in Heart Failure With Preserved Ejection Fraction

Heart failure with preserved ejection (HFpEF) and diabetes mellitus (DM) commonly co-exist. However, it is unclear if DM modifies the haemodynamic and cardiometabolic phenotype in patients with HFpEF. We aimed to interrogate the haemodynamic and cardiometabolic effects of DM in HFpEF. We compared the haemodynamic and metabolic profiles of non-DM patients and patients with DM-HFpEF at rest and during exercise using right heart catheterisation and mixed venous blood gas analysis. Of 181 patients with HFpEF, 37 (20%) had DM. Patients with DM displayed a more adverse exercise haemodynamic response vs HFpEF alone (mean pulmonary arterial pressure: 47 mmHg [interquartile range {IQR} 42-55] vs 42 [38-47], p<0.001; workload indexed pulmonary capillary wedge pressure indexed: 0.80 mmHg/W [0.44-1.23] vs 0.57 [0.43-1.01], p=0.047). HFpEF-DM patients had a lower mixed venous oxygen saturation at rest (70% [IQR 66-73] vs 72 [69-75], p=0.003) and were unable to enhance O2 extraction to the same extent (Δ-28% [-33 to -15] vs -29 [-36 to -21], p=0.029), this occurred at a 22% lower median workload. Resting mixed venous lactate levels were higher in those with DM (1.5 mmol/L [IQR 1.1-1.9] vs 1 [0.9-1.3], p<0.001), and during exercise indexed to workload (0.09 mmol/L/W [0.06-0.13] vs 0.08 [0.05-0.11], p=0.018). Concurrent diabetes and HFpEF was associated with greater metabolic responses at rest, with enhanced wedge driven pulmonary hypertension and relative lactataemia during exercise without appropriate augmentation of oxygen consumption.

Cardiac Magnetic Resonance Studies in a Large Animal Model that Simulates the Cardiac Abnormalities of Human Septic Shock.

Septic shock, in humans and in our well-established animal model, is associated with increases in biventricular end diastolic volume (EDV) and decreases in ejection fraction (EF). These abnormalities occur over 2 days and reverse within 10 days. Septic non-survivors do not develop an increase in EDV. The mechanism for this cardiac dysfunction and EDV differences is unknown. Purpose-bred beagles randomized to receive intrabronchial Staphylococcus aureus (n=27) or saline (n=6) were provided standard ICU care including sedation, mechanical ventilation, and fluid resuscitation to a pulmonary arterial occlusion pressure of over 10mmHg. No catecholamines were administered. Over 96h, cardiac magnetic resonance imaging, echocardiograms, and invasive hemodynamics were serially performed, and laboratory data was collected. Tissue was obtained at 66h from six septic animals. From 0-96h after bacterial challenge, septic animals vs. controls had significantly increased left ventricular wall edema (6%) and wall thinning with loss of mass (15%) which was more pronounced at 48h in non-survivors than survivors. On histology, edema was located predominantly in myocytes, the interstitium, and endothelial cells. Edema was associated with significantly worse biventricular function (lower EFs), ventricular-arterial coupling, and circumferential strain. In septic animals, from 0-24h, the EDV decreased from baseline and, despite cardiac filling pressures being similar, decreased significantly more in non-survivors. From 24-48h, all septic animals had increases in biventricular chamber sizes. Survivors biventricular EDVs were significantly greater than baseline and in non-survivors, where biventricular EDVs were not different from baseline. Preload, afterload, or HR differences did not explain these differential serial changes in chamber size. Systolic and diastolic cardiac dysfunction during sepsis is associated with ventricular wall edema. Rather than differences in preload, afterload, or heart rate, structural alterations to the ventricular wall best account for the volume changes associated with outcome during sepsis. In non-survivors, from 0-24h, sepsis induces a more severe diastolic dysfunction, further decreasing chamber size. The loss of left ventricular mass with wall thinning in septic survivors may, in part explain, the EDV increases from 24-48h. However, these changes continued and even accelerated into the recovery phase consistent with a reparative process rather than ongoing injury.

Pulmonary Vein Flow Morphology After Transcatheter Mitral Valve Edge-to-Edge Repair as Predictor of Survival

Data on the prognostic factors after mitral valve (MV) transcatheter edge-to-edge repair (TEER;MV-TEER) are limited. Pulsed-wave Doppler interrogation of pulmonary vein flow (PVF) is a convenient method to assess the hemodynamic burden of residual mitral regurgitation (MR), which could be of utility as a predictor of outcomes. Patients that underwent MV-TEER between May 2014 and December 2021 at our institution were evaluated. Pulmonary vein flow patterns post-MV-TEER were reviewed on the procedural transesophageal echocardiogram and classified as normal (systolic dominant or codominant) or abnormal (systolic blunting or reversal). The PVF pattern was correlated with all-cause mortality at follow-up. Two-hundred sixty-five patients had diagnostic PVF post-MV-TEER, with 73 (27.5%) categorized as normal and 192 (72.5%) categorized as abnormal. Patients with abnormal PVF morphology were more likely to have atrial fibrillation (70% vs 42%, P<.001) and greater than moderate residual MR (16% vs 3%, P=.01) and had higher mean left atrial pressure (18.1±5.0 vs 15.9±4.2mm Hg, P=.002) and left atrial V wave (26.6±8.5 vs 21.4±7.3mm Hg, P<.001) postprocedure. In multivariable analysis, abnormal PVF morphology post-MV-TEER was independently associated with mortality at follow-up (hazard ratio= 1.70; 95% CI, 1.06-2.74; P=.03) after correction for end-stage renal disease, atrial fibrillation, and residual MR. Results were similar in subgroups of patients with moderate or less and those with mild or less residual MR. Pulmonary vein flow morphology is a simple and objective tool to assess MR severity immediately post-MV-TEER and offers important prognostic information to optimize procedural results. Additional studies are needed to determine whether patients with abnormal PVF pattern post-MV-TEER would benefit from more intensive goal-directed medical therapy postprocedure.

Evaluating the Efficacy of Interatrial Shunt Devices in Heart Failure With Preserved Ejection Fraction: A Systematic Review and Meta-Analysis.

Heart failure with preserved ejection fraction (HFpEF) is a prevalent and challenging condition with limited therapeutic options. This meta-analysis aims to assess the feasibility and effectiveness of interatrial shunt devices (IASD) in the treatment of HFpEF, focusing on key hemodynamic parameters and clinical outcomes. Six clinical trials, encompassing 324 patients, were included in this analysis. The results showed a significant reduction in pulmonary capillary wedge pressure (PCWP) at rest after IASD implantation, with a mean difference of 1.55 mm Hg. PCWP during exercise also exhibited a decrease, indicating improved exercise tolerance. However, there was an increase in mean right atrial pressure following IASD implantation. These findings suggest that IASD implementation can effectively lower left atrial pressure, a critical target in HFpEF management. This results in substantial clinical improvements, including enhanced New York Heart Association class, quality of life, and 6-minute walk distance. Echocardiographic assessments revealed a reduction in left ventricular end-diastolic volume index and stable right ventricular changes. The meta-analysis underscores the potential benefits of IASD in ameliorating the symptoms and clinical outcomes of HFpEF patients. The increase in mean right atrial pressure warrants further investigation into its effects on right heart function. Additionally, this analysis emphasizes the need for larger, randomized clinical trials to validate these findings and determine optimal patient selection criteria. IASD implantation holds promise as a therapeutic option for HFpEF, offering the potential to improve the quality of life and functional status of affected patients. However, further research is imperative to confirm its efficacy relative to existing treatments and to address concerns regarding its impact on right heart function. This meta-analysis contributes to a deeper understanding of IASD's role in HFpEF management.

Influence of myocardial contractility therapy for advanced heart failure

With more than 5 million patients’ diagnosed with heart failure (HF) and more than 1 million hospitalizations each year, HF continues to have a significant impact on health-care resources. Despite treatment, a significant number of patients continue to have progressive HF symptoms, classified as Class III or IV. The aim of this study was to compare different inotropic therapy for patients of End-Stage Heart Failure. When persistent intravenous access was used and acute hemodynamic improvement was established, the durable medical equipment (DME) benefit category reimbursed 80% of outpatient inotropic medication and supplies for HF. Acute hemodynamic improvement was defined as a 20% reduction in pulmonary capillary wedge pressure and/or a 20% increase in cardiac index, both of which were related to a decrease in dyspnea. The Centers for Medicaid and Medicare Services contracted with regional carriers to run the program. The amounts reimbursed per beneficiary for inotrope and supplies (not adjusted for differential follow-up) were essentially representative of the inotrope cost. Dobutamine, milrinone, and supplies had mean (and median) amounts of 5025 (1168), 87781 (31440), and 7284 (3131), respectively. We found that patients who received this medication had a relatively high death rate, however not as high as people who received chemotherapy. Milrinone-treated patients were compensated more for hospitalizations both before and after starting the inotrope. In addition, the milrinone group had a higher level of digoxin use in the background. Nonetheless, there is an early decrease in overall expenditures following inotrope initiation, which can be attributed to a decrease in hospitalization. Considering the lack of double-blind trials comparing inotropes to placebo or dobutamine to milrinone, decisions regarding the use of inotropes, the type of inotrope used, and the duration of treatment should take into account the impact on resources.

Exercise catheterization in adults post-Fontan with normal and abnormal haemodynamic criteria: Insights into normal Fontan physiology.

The normal (i.e. expected) haemodynamics in adults post-Fontan remain poorly delineated. Moreover, the definitions of elevated exercise pulmonary artery (PA) and PA wedge pressure (PAWP) for this population have not been described. Seventy-two adults post-Fontan undergoing exercise catheterization were categorized into abnormal (Group I, n = 59; defined as resting mean PA ≥14 mmHg and/or PAWP ≥12 mmHg, ΔPAWP/Δsystemic flow [Qs] >2 mmHg/L/min, and/or ΔPA/Δpulmonary flow >3 mmHg/L/min) and normal (Group II, n = 13) haemodynamics. Thirty-nine patients with non-cardiac dyspnoea (NCD) were included as controls. There was no difference in exercise arterial oxygen saturation (87% [81-92] vs. 89% [85-93], p = 0.29), while exercise PA pressure (27 [23-31] vs. 16 [14.5-19.5] mmHg, p < 0.001) and PAWP were higher (21 [18-28] vs. 12 [8-14] mmHg, p < 0.001) in Group I. At peak exercise, Group I had lower heart rate (97 [81-120] vs. 133 [112.5-147.5] bpm, p < 0.001) and Qs response (67.3 [43.8-93.1] vs. 105.9 (82-118.5) % predicted, p < 0.001) than Group II. Exercise superior vena cava pressures were higher (16 [14-22.5] vs. 5.5 [3-7.3] mmHg, p < 0.001) and arterial oxygen saturation lower (89% [85-93] vs. 97% [96-98], p < 0.001) in Group II compared to NCD, while no differences in PAWP, stroke volume index, heart rate, or Qs response were seen. If defined as two standard deviations above mean values for Group II, elevated PAWP and mean PA pressure post-Fontan would correspond to 20.6 mmHg and 25.8 mmHg, respectively. PAWP >20 mmHg and mean PA pressure >25 mmHg could be used to define elevated values during exercise in adults post-Fontan. The major discrepancy in exercise haemodynamics among Group II compared to controls appears to be the degree of systemic venous hypertension and arterial desaturation.

Mitral E-wave to stroke volume ratio displays stronger diagnostic performance to identify elevated left ventricular filling pressures than mitral E/e' during passive leg lift: A cross-sectional study employing simultaneous echocardiography and catheterization.

Elevated filling pressure is a hallmark of heart failure (HF) and portends poor prognosis. Accurate diagnosis is challenging, given that patients with normal filling pressure at rest develop disproportionate elevation with sudden preload increase. We aimed to test the accuracy of the ratio between mitral inflow velocity (E) and left ventricular stroke volume (SV) to identify patients with elevated filling pressure with passive leg lifting (PLL) and compare this with other echocardiographic surrogates of filling pressure. Doppler echocardiography and right heart catheterization (RHC) were simultaneously performed in 37 patients (11 males, mean age 67±12 years) with exertional dyspnea. Twenty-six healthy controls (14 males, mean age 60±12 years) were added as reference. SV, cardiac output (CO), tricuspid regurgitation peak gradient (TRG), mitral E-wave (E)and early myocardial velocity (e') were obtained at rest and with PLL. E/SV, E/CO and E/e' were calculated and correlated with invasive pulmonary capillary wedge pressures (PCWP) with PLL. During PLL, E/SV (AUC=0.94) displayed stronger diagnostic ability to identify PCWP>15mmHg than E/e' (AUC=0.81), mitral E/A ratio (0.76) and resting invasive PCWP (0.84). An E/SV cutoff of>1.0 showed 88% sensitivity and 75% specificity to identify elevated PCWP. Further, 10 patients (27%) were reassigned during PLL from normal to postcapillary pulmonary hypertension (postCPH), and 6 patients (16%) switched diagnosis from precapillary PH (preCPH) to postCPH. The novel E/SV ratio identifies patients with elevated PCWP with PLL and displays stronger diagnostic performance than routinely utilized echocardiographic measures such as E/e' in addition to resting, catheterization derived PCWP.

Pulmonary Artery Wedge Pressure Can Underestimate Direct Pulmonary Vein Pressure in Pediatric Pulmonary Vein Stenosis

BackgroundPulmonary artery wedge pressure (PAWP) can underestimate directly measured pulmonary vein pressure (PVP) as demonstrated in animal studies and human case reports. This concept has not been validated in a larger cohort of pediatric patients with pulmonary vein stenosis (PVS). MethodsPediatric patients who underwent cardiac catheterization for PVS at a single center from January 1, 2018, to March 31, 2023, were retrospectively reviewed. Mismatch between the PAWP and directly measured PVP or LA pressure was defined as >3 mm Hg. Preintervention angiography was reviewed and percent stenosis calculated. ResultsTwenty-six patients met inclusion criteria; 51 lower pulmonary veins (34 left, 17 right) from 42 catheterizations were evaluated. Significant PVS (≥30% stenosis) was seen in 38/51 (75%) veins, and 9/51 (18%) veins had no angiographic narrowing (0% stenosis). PAWP-PVP mismatch occurred in 37/51 (73%) veins with a median difference of 8 mm Hg (IQR, 6-12). Of these, PAWP was equal to LA pressure in 26 instances, all of which had significant PVS (median % stenosis 54 [IQR, 45-60]). Six of the cases with PAWP-PVP mismatch, PVS (range, 41%-70% stenosis), and no PAWP-LA mismatch reported both a proximal and distal segmental PAWP. In all 6 instances, there was no distal PAWP-PVP mismatch (median difference 1 mm Hg [range, 0-3]). ConclusionsIn this single-center study of pediatric patients with PVS, PAWP significantly underestimated directly measured PVP in lower pulmonary veins. Balloon wedge or end hole catheter position in a distal lobar segment may more accurately estimate the PVP.

A Novel Pumping Principle for a Total Artificial Heart.

Total artificial hearts (TAH) serve as a temporary treatment for severe biventricular heart failure. The limited durability and complication rates of current devices hamper long-term cardiac replacement. The aim of this study was to assess the feasibility of a novel valveless pumping principle for a durable pulsatile TAH (ShuttlePump). The pump features a rotating and linearly shuttling piston within a cylindrical housing with two in- and outlets. With a single moving piston, the ShuttlePump delivers pulsatile flow to both systemic and pulmonary circulation. The pump and actuation system were designed iteratively based on analytical and in silico methods, utilizing finite element methods (FEM) and computational fluid dynamics (CFD). Pump characteristics were evaluated experimentally in a mock circulation loop mimicking the cardiovascular system, while hemocompatibility-related parameters were calculated numerically. Pump characteristics cover the entire required operating range for a TAH, providing 2.5-9 L/min of flow rate against 50-160 mmHg arterial pressures at stroke frequencies of 1.5-5 Hz while balancing left and right atrial pressures. FEM analysis showed mean overall copper losses of 8.84 W, resulting in a local maximum blood temperature rise of <2 K. The CFD results of the normalized index of hemolysis were 3.57 mg/100 L, and 95% of the pump's blood volume was exchanged after 1.42 s. This study indicates the feasibility of a novel pumping system for a TAH with numerical and experimental results substantiating further development of the ShuttlePump.

Diastology in the intensive care unit: Challenges for the assessment and future directions.

Myocardial dysfunction is common in patients admitted to the intensive care unit (ICU). Septic disease frequently results in cardiac dysfunction, and sepsis represents the most common cause of admission and death in the ICU. The association between left ventricular (LV) systolic dysfunction and mortality is not clear for critically ill patients. Conversely, LV diastolic dysfunction (DD) seems increasingly recognized as a factor associated with poor outcomes, not only in sepsis but also more generally in critically ill patients. Despite recent attempts to simplify the diagnosis and grading of DD, this remains relatively complex, with the need to use several echocardiographic parameters. Furthermore, the current guidelines have several intrinsic limitations when applied to the ICU setting. In this manuscript, we discuss the challenges in DD classification when applied to critically ill patients, the importance of left atrial pressure estimates for the management of patients in ICU, and whether the study of cardiac dysfunction spectrum during critical illness may benefit from the integration of left ventricular and left atrial strain data to improve diagnostic accuracy and implications for the treatment and prognosis.

Left atrial appendage inversion: First computational study to shed light on the phenomenon

Inversion of the left atrial appendage is a rare phenomenon, which may occur during the de-airing maneuvers associated to routinely performed surgery procedures, such as cardiopulmonary bypass or left ventricular assist device implantation. In this case, the body of the inverted appendage can obstruct the mitral valve leading to severe complications. The mechanisms are still poorly known, and more specific studies are needed to better understand its causes and identify mitigating strategies. The current study attempts to gain a better comprehension of the conditions and the factors favourable to left atrial appendage inversion. Four patient specific appendage morphologies, obtained from computerised tomography and representative of the main typologies commonly used for the appendage classification (chicken wing, cactus, cauliflower, and windsock), were used for the study. The numerical models were subjected to the same loading pattern, made of subsequent different pressure curves.Results show that the morphologies invert and recover their original anatomical configuration at different pressure loads, indicating that their tendency to invert is associated to their specific morphological features. Moreover, the analysis highlights that, although restoring the physiological left atrium pressure is not sufficient to induce appendage recovery, pressures well below the ventricular ones can induce the return to the natural configuration.All models recovered the anatomical configuration at pressures well below the ventricular pressure (about 100 mmHg), suggesting that basic trans-catheter maneuvers, e.g. producing temporary mitral regurgitation, could be attempted to correct the appendage configuration, prior to opt for more invasive surgical approaches.

Case of rheumatic heart disease and severe mitral stenosis, managed by balloon mitral valvuloplasty in pregnancy

Mitral stenosis (MS) is a progressive situation caused by obstruction of blood flow across the mitral valve from the left atrium to the left ventricle. It is one of the most common valvular heart lesions found during pregnancy. The chances of significant maternal and fetal morbidity and mortality are more in the case of severe MS. Balloon mitral valvuloplasty (BMV) is a life-saving procedure in pregnancy instead of surgical correction. We are presenting the case of a 24-week pregnant woman with severe MS. She developed pulmonary edema and had undergone successful BMV which allowed her to tolerate her pregnancy decently. It leads to a decrease in the left atrial pressure as well as pulmonary arterial pressure. The patient underwent normal delivery uneventfully. Antibiotics were used with proper consultation and the patient was treated conservatively with excellent maternal and fetal outcomes. BMV is turns out to be a life-saving therapy for severe MS complicated by pulmonary edema.

Diagnosis of heart failure with preserved ejection fraction

Heart failure with preserved ejection fraction (HFpEF) currently causes about half of the heart failure related hospitalizations. With the aging of the population and increasing prevalence of risk factors and comorbidities, such as arterial hypertension, diabetes mellitus and obesity, HFpEF prevalence is expected to increase as well. With regards to quality of life, overall morbidity, and mortality, HFpEF patients have a similarly adverse prognosis as patients with heart failure with reduced ejection fraction. The leading symptoms of exertional dyspnea and exercise intolerance with concomitant clinical signs of heart failure should, therefore, prompt diagnostic tests to exclude or confirm HFpEF. Considering the main pathophysiological mechanisms, echocardiography is crucial to non-invasively identify signs of left ventricular (LV) hypertrophy, impaired myocardial relaxation, and elevated filling pressures. Elevated NT-proBNP may furthermore indicate increased LV wall stress and volume overload. If the results of these investigations are inconclusive, parameters of elevated filling pressures can be measured invasively by right or left heart catheterization. High pulmonary capillary wedge pressure (PCWP) or left ventricular end-diastolic pressure (LVEDP) may confirm a HFpEF diagnosis. Ongoing studies are investigating potential distinct phenotypes within the HFpEF patient group.

Investigating the importance of left atrial compliance on fluid dynamics in a novel mock circulatory loop.

The left atrium (LA) hemodynamic indices hold prognostic value in various cardiac diseases and disorders. To understand the mechanisms of these conditions and to assess the performance of cardiac devices and interventions, in vitro models can be used to replicate the complex physiological interplay between the pulmonary veins, LA, and left ventricle. In this study, a comprehensive and adaptable in vitro model was created. The model includes a flexible LA made from silicone and allows distinct control over the systolic and diastolic functions of both the LA and left ventricle. The LA was mechanically matched with porcine LAs through expansion tests. Fluid dynamic measures were validated against the literature and pulmonary venous flows recorded on five healthy individuals using magnetic resonance flow imaging. Furthermore, the fluid dynamic measures were also used to construct LA pressure-volume loops. The in vitro pressure and flow recordings expressed a high resemblance to physiological waveforms. By decreasing the compliance of the LA, the model behaved realistically, elevating the a- and v-wave peaks of the LA pressure from 12 to 19mmHg and 22 to 26mmHg, respectively, while reducing the S/D ratio of the pulmonary venous flowrate from 1.5 to 0.3. This model provides a realistic platform and framework for developing and evaluating left heart procedures and interventions.

Risk Factors for Atrial Fibrillation in the Dog: A Systematic Review.

Different risk factors for atrial fibrillation (AF) development have been identified in numerous studies on humans, but this information is less clearly available on the dog. The aim of this systematic review is to determine the risk factors for AF in the dog. Following the PRISMA 2020 guidelines, we conducted a comprehensive search using the Web of Science and Scopus databases for articles reporting on cases of spontaneously occurring AF in dogs. The level of evidence was assessed using the Evidence Quality Grading System of the National Institute of Health. One thousand forty-three studies were initially identified, and twenty of them were included in this systematic review involving 2,359,275 dogs, of which 4807 showed spontaneously occurring AF. Genetics, for the Irish Wolfhound, increased body weight, and left atrial enlargement were the main risk factors for the development of AF in dogs with different cardiac diseases, particularly myxomatous mitral valve disease (MMVD) and dilated cardiomyopathy (DCM). However, some differences were found between these two cardiac diseases regarding additional risk factors. In particular, the presence of congestive heart failure and echocardiographic evidence of increased left atrial pressure or the presence of right atrial enlargement emerged as risk factors in dogs with MMVD or DCM, respectively. Furthermore, significant differences in risk factors were observed between dogs and humans. In particular, advanced age and male sex are not reliable indicators of an increased risk of AF in dogs.

Mitral Annulus Calcium Score in Patients With Calcific Mitral Stenosis Undergoing Invasive Hemodynamic Assessment.

Aortic valve calcium score is associated with hemodynamic severity of aortic stenosis. Whether this association is present in calcific mitral stenosis remains unknown. 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 cm2. 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). 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.