Absence of right ventricular isovolumic relaxation in open-chest anesthetized dogs

1992 ◽  
Vol 263 (5) ◽  
pp. H1587-H1590 ◽  
Author(s):  
E. S. Myhre ◽  
B. K. Slinker ◽  
M. M. LeWinter
Keyword(s):  
Right Ventricular ◽  
Left Ventricular ◽  
Right Atrial ◽  
Relative Timing ◽  
Relaxation Period ◽  
First Derivative ◽  
Open Chest ◽  
Anesthetized Dogs ◽  
The Right ◽  
Isovolumic Relaxation

During the left ventricular (LV) pump cycle, peak negative first derivative of pressure vs. time (dP/dt) occurs very close to the end of LV ejection, and there is a well-defined isovolumic relaxation period. Despite similarities between the right ventricular (RV) and LV pump cycles, recent studies indicate uncertainty as to whether peak negative RV dP/dt occurs simultaneously with RV end ejection and whether there is an isovolumic relaxation period during the RV pump cycle. To study these questions, we recorded relative timing of peak negative RV dP/dt, RV end ejection, and right atrial-RV pressure crossover in the open-chest anesthetized dog. The data demonstrate that peak negative RV dP/dt occurs an average of 60 ms before end ejection and that there is no RV isovolumic relaxation period. These findings have implications for the possible use of peak negative RV dP/dt as a marker of RV end ejection and for how time constants of pressure decay obtained during RV relaxation can be interpreted.

Right Heart Function during Left Ventricular Assistance in an Open-Chest Porcine Model of Acute Right Heart Failure

1994 ◽  
Vol 17 (4) ◽  
pp. 224-229 ◽  
Author(s):  
Y. Abe ◽  
K. Kotoh ◽  
P.H. Deleuze ◽  
M. Miyama ◽  
G.J. Cooper ◽  
...  
Keyword(s):  
Heart Failure ◽  
Right Ventricular ◽  
Right Heart Failure ◽  
Left Ventricular ◽  
Volume Loading ◽  
Right Heart ◽  
Open Chest ◽  
The Right ◽  
Ventricular Assistance ◽  
Left Ventricular Assistance

Changes in the right ventricular function measured with a thermodilution ejection fraction catheter have been recorded in open-chest normal pigs and pigs with acute right heart failure (RVF) undergoing left ventricular assistance with a pneumatic-sactype device (LVAD). To produce acute right heart failure, 5 pigs underwent ligation of the right ventricular free wall coronary arteries. Compared with normal pigs, cardiac output in ligated pigs fell by 21% (7.5 ± 0.5 vs 9.5 ± 1.2 L/min; p < 0.05) and the right ventricular end diastolic pressure rose (11.4 ± 2.6 vs 5.7 ± 3.6 vs mmHg: p <0.05). With the left ventricular assist device connected, the right atrial pressure was increased to 3, 5, 7, 10 and 12 mmHg by volume loading while maintaining the haematocrit at 35 ± 6%. The right ventricular stroke work index (RVSWI) increased with volume loading in normal pigs. In RVF pigs, RVSWI increased significantly with the LVAD (59.2 ± 5.8 vs 23.5 ± 7.8 mmHg ml/min/kg, p<0.01), approaching that of normal pigs (62.3 ± 4.8 mmHg ml/min/kg). Similar changes were observed in the cardiac output and right ventricular stroke volume. These results show that, in this model of open-chest, mild, acute right heart failure, left ventricular assistance allows right ventricular function to return to normal, despite volume overloading, by decreasing right ventricular after load and increasing right ventricular compliance

scholarly journals Sleep disordered breathing and enlargement of the right heart after myocardial infarction

2014 ◽  
Vol 45 (3) ◽  
pp. 680-690 ◽  
Author(s):  
Stefan Buchner ◽  
Michael Eglseer ◽  
Kurt Debl ◽  
Andrea Hetzenecker ◽  
Andreas Luchner ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Right Ventricular ◽  
Sleep Disordered Breathing ◽  
Left Ventricular ◽  
Right Atrial ◽  
Right Heart ◽  
Systolic Volume ◽  
End Diastolic Volume ◽  
End Systolic Volume ◽  
The Right

Structural and functional integrity of the right heart is important in the prognosis after acute myocardial infarction (AMI). The objective of this study was to assess the impact of sleep disordered breathing (SDB) on structure and function of the right heart early after AMI.54 patients underwent cardiovascular magnetic resonance 3–5 days and 12 weeks after AMI, and were stratified according to the presence of SDB, defined as an apnoea–hypopnoea index of ≥15 events·h−1.12 weeks after AMI, end-diastolic volume of the right ventricle had increased significantly in patients with SDB (n=27)versusthose without (n=25) (mean±sd14±23%versus0±17%, p=0.020). Multivariable linear regression analysis accounting for age, sex, body mass index, smoking, left ventricular mass and left ventricular end-systolic volume showed that the apnoea–hypopnoea index was significantly associated with right ventricular end-diastolic volume (B-coefficient 0.315 (95% CI 0.013–0.617); p=0.041). From baseline to 12 weeks, right atrial diastolic area increased more in patients with SDB (2.9±3.7 cm2versus1.0±2.4 cm2, p=0.038; when adjusted for left ventricular end systolic volume, p=0.166).SDB diagnosed shortly after AMI predicts an increase of right ventricular end-diastolic volume and possibly right atrial area within the following 12 weeks. Thus, SDB may contribute to enlargement of the right heart after AMI.

Right ventricular distension and left ventricular compliance

1981 ◽  
Vol 240 (1) ◽  
pp. H87-H98 ◽  
Author(s):  
B. H. Lorell ◽  
I. Palacios ◽  
W. M. Daggett ◽  
M. L. Jacobs ◽  
B. N. Fowler ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Time Course ◽  
Diastolic Pressure ◽  
Left Ventricular ◽  
Leftward Shift ◽  
Ventricular Compliance ◽  
Left Ventricular Compliance ◽  
The Right ◽  
Relationship Of ◽  
Isovolumic Relaxation

The constraint of the right ventricle (RV) on the end-diastolic pressure-volume (PV) relationship of the nonischemic and ischemic left ventricle (LV) was studied. The model used was the isovolumic beating LV, with separately perfused ejecting RV with controlled RV distension. The effect of augmented RV distension on the nonischemic LV PV relationship was examined. A change from mild [right ventricular end-diastolic pressure (RVEDP) = 1.5 mm Hg] to severe (RVEDP = 16 mmHg) RV distension resulted in a significant leftward shift of the LV PV relationship. Ischemia was produced for 90 min by reducing flow in the cannulated left main coronary artery and the effect of two levels of stable RV distension on the PV relationship of the ischemic LV was examined. Mild RV distension and moderate (RVEDP = 6 mmHg) RV distension were used. In both groups, there was a progressive leftward shift in the LV PV relationship that was significant by 60 min of ischemia. No change was seen in nonischemic controls. Ventricular relaxation, as described by the time constant of isovolumic relaxation, T, was impaired throughout ischemia but was not sufficiently prolonged to explain the above changes. Thus, the time course of change in the LV PV relationship during ischemia differs from that previously reported after pacing-induced ischemia in humans. Neither the external constraint of the RV nor incomplete relaxation explains this difference.

Influence of the right ventricle on canine left ventricular function with PEEP

1982 ◽  
Vol 52 (1) ◽  
pp. 254-259 ◽  
Author(s):  
S. M. Scharf ◽  
R. Brown
Keyword(s):  
Pulmonary Arterial Pressure ◽  
Arterial Occlusion ◽  
Left Ventricular ◽  
Right Atrial ◽  
Lv Function ◽  
Stroke Work ◽  
Anesthetized Dogs ◽  
Pulmonary Arterial ◽  
The Right ◽  
Extracorporeal Bypass

In anesthetized dogs we evaluated the influence of increased right ventricular (RV) pressures on left ventricular (LV) function by comparing the hemodynamic effects of increases in RV afterload (pulmonary arterial pressure) produced by positive end-expiratory pressure (PEEP) with those due to pulmonary arterial occlusion (PAO). Left atrial (Pla) and right atrial (Pra) pressures increased with PEEP and PAO [for Pla: 3.1 +/- 0.7 Torr (PEEP), 2.4 +/- 0.9 Torr (PAO); for Pra: 2.9 +/- 0.4 Torr (PEEP), 3.1 +/- 1.2 Torr (PAO)]. RV septal-free wall dimension (RVD) increased, and LV septal-posterolateral dimension (L2) decreased with both conditions [increases in RVD: 1.9 +/- 0.3 mm (PEEP), 2.2 +/- 0.5 mm (PAO); decrease in L2: 1.1 +/- 0.4 mm (PEEP), 0.9 +/- 0.3 mm (PAO)]. Extracorporeal bypass of the great veins did not alter these findings. LV function curves showed less stroke work at any Pla during PEEP, this being unaffected by vagotomy. When the RV was bypassed, there were no PEEP or PAO related changes in Pla or LV function. Thus diminished LV function with PEEP is probably due to the influence on the LV of a stressed RV in this situation.

Sudden-onset severe presyncope in a 67-year-old man

Heart ◽  
2018 ◽  
pp. heartjnl-2018-314118
Author(s):  
Katie Hannah Sanders ◽  
Claire A Martin ◽  
Munmohan Virdee
Keyword(s):  
Right Ventricular ◽  
Chest Radiograph ◽  
Atrioventricular Node ◽  
Persistent Atrial Fibrillation ◽  
Cardiac Resynchronisation Therapy ◽  
Sudden Onset ◽  
Left Ventricular ◽  
Right Atrial ◽  
List Type ◽  
The Right

A 67-year-old man presented to the emergency department with sudden onset of severe presyncope. He reported that he had a permanent pacemaker implanted in 2006 following atrioventricular node ablation for persistent atrial fibrillation (AF). After suffering increasing shortness of breath, he underwent upgrade to cardiac resynchronisation therapy (CRT) in 2016. He denied any recent falls, interventions or changes in medication. ECG monitoring showed AF with a broad ventricular escape rhythm at around 25 bpm with pauses of up to 3 s. Placement of a magnet over the device resulted in pacing (figure 1A). The implanted device (Medtronic Syncra C2TR01) was interrogated (figure 1B), and a chest radiograph was obtained (figure 2). Figure 1(A) Twelve-lead ECG demonstrating intrinsic rhythm and pacing after application of magnet. (B) Device interrogation with right ventricular threshold test.Figure 2(C) Anteroposterior chest radiograph demonstrating lead position on admission.QuestionWhat was the cause of this presentation?Noise oversensing on the right ventricular (RV) lead due to lead fracture.The RV septal lead has displaced into the right atrial (RA).RA and RV leads were switched in the can during the CRT upgrade.Increase in threshold of RV and left ventricular (LV) leads resulting in loss of capture.

Isoflurane and Desflurane Impair Right Ventricular–Pulmonary Arterial Coupling in Dogs

2004 ◽  
Vol 101 (6) ◽  
pp. 1357-1362 ◽  
Author(s):  
François Kerbaul ◽  
Benoît Rondelet ◽  
Sophie Motte ◽  
Pierre Fesler ◽  
Ives Hubloue ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Characteristic Impedance ◽  
Coupling Efficiency ◽  
Left Ventricular ◽  
Dependent Manner ◽  
Anesthetized Dogs ◽  
Pulmonary Arterial ◽  
Fraction Of Inspired Oxygen ◽  
The Right ◽  
Inspired Oxygen

Background Halogenated anesthetics depress left ventricular function, but their effects on the right ventricle have been less well studied. Therefore, the authors studied the effects of isoflurane and desflurane on pulmonary arterial (PA) and right ventricular (RV) properties at baseline and in hypoxia. Methods Right ventricular and PA pressures were measured by micromanometer catheters, and PA flow was measured by an ultrasonic flow probe. PA mechanics were assessed by flow-pressure relations and by impedance spectra derived from flow and pressure waves. RV contractility was assessed by end-systolic elastance (Ees), RV afterload was assessed by effective PA elastance (Ea), and RV-PA coupling efficiency was assessed by the Ees:Ea ratio. Anesthetized dogs were randomly assigned to increasing concentrations (0.5, 1, and 1.5 times the minimum alveolar concentration) of isoflurane (n = 7) or desflurane (n = 7) in hyperoxia (fraction of inspired oxygen, 0.4) and hypoxia (fraction of inspired oxygen, 0.1). Results Isoflurane and desflurane had similar effects. During hyperoxia, both anesthetics increased PA resistance and characteristic impedance, increased Ea (isoflurane, from 0.82 to 1.44 mmHg/ml; desflurane, from 0.86 to 1.47 mmHg/ml), decreased Ees (isoflurane, from 1.09 to 0.66 mmHg/ml; desflurane, from 1.10 to 0.72 mmHg/ml), and decreased Ees:Ea (isoflurane, from 1.48 to 0.52; desflurane, from 1.52 to 0.54) in a dose-dependent manner (all P &lt; 0.05). Hypoxia increased PA resistance, did not affect characteristic impedance, increased afterload, and increased contractility. During hypoxia, isoflurane and desflurane had similar ventricular effects as during hyperoxia. Conclusions Isoflurane and desflurane markedly impair RV-PA coupling efficiency in dogs, during hyperoxia and hypoxia, both by increasing RV afterload and by decreasing RV contractility.

scholarly journals Automated evaluation of the right-sided heart function and geometry using deep learning

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
A Karuzas ◽  
K Sablauskas ◽  
R Zvirblyte ◽  
L Skrodenis ◽  
E Teleisyte ◽  
...  
Keyword(s):  
Deep Learning ◽  
Right Ventricular ◽  
Heart Function ◽  
Left Ventricular ◽  
Doppler Imaging ◽  
Right Atrial ◽  
Left Ventricular Ejection ◽  
Routine Practice ◽  
Ventricular Ejection Fraction ◽  
The Right

Abstract Funding Acknowledgements Type of funding sources: None. INTRODUCTION  Deep learning (DL) has been successfully applied in the automated assessment of some transthoracic echocardiography (TTE) parameters such as left-ventricular ejection fraction. Nevertheless, automation of the right-sided heart assessment has not been widely studied, partially due to the relative difficulty involved in some of the right-sided heart measurement evaluation and time constraints in routine practice. Here we have explored the feasibility of a DL-based system capable of performing different tasks involved in the right-sided heart functional and geometric evaluation. PURPOSE  To develop a DL-based system assessing right atrium (RA) and right ventricle (RV) functional and geometric parameters and compare its accuracy to board-certified cardiologists. METHODS A total of 2,014 frames from 349 patients (with various indications for TTE) were used to train and validate four convolutional neural networks (CNNs) to perform either segmentation or landmark detection across four different TTE views: apical four-chamber (A4Ch), parasternal long-axis (PLAX), M-mode of tricuspid annulus and tissue Doppler imaging (TDI) of the right ventricular lateral wall. The CNNs were optimised to perform different right-sided heart measurements, namely, right atrial area in end-systole (RAA) and fractional area change (FAC) of RV in A4Ch view, proximal right ventricular outflow tract diameter (pRVOT) in PLAX view, tricuspid annular plane systolic excursion (TAPSE) in M-mode and S’ in TDI. Model performance was compared with two board-certified cardiologists using their average measurements on 20 test set patients.  RESULTS CNN predicted pRVOT diameter with a mean absolute error (MAE) of 1.02 mm and root mean squared error (RMSE) of 3.08 mm. The intersection over union (IoU) for the segmentation of RV and RA was 0.89 and 0.87, respectively. We then used  RV and RA segmentation predictions to calculate additional parameters which resulted in RMSE of 8.34% for FAC and 4.93cm2 for RAA. In the M-mode and TDI, the model achieved RMSE of 4.48 mm and 0.84 cm/s for the detection of TAPSE and S’, respectively. CONCLUSIONS We have demonstrated the feasibility of a DL-based system performing different measurements involved in right-sided heart evaluation. In a routine practice, where limited time resources might be available, such could assist in the thorough assessment of the right-sided heart geometry and function. Additional studies using cardiac magnetic resonance imaging to establish more precise accuracy of such systems is needed.

scholarly journals External assessment of the EUROMACS right-sided heart failure risk score

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hirak Shah ◽  
Thomas Murray ◽  
Jessica Schultz ◽  
Ranjit John ◽  
Cindy M. Martin ◽  
...  
Keyword(s):  
Heart Failure ◽  
Right Ventricular ◽  
Risk Score ◽  
Pressure Ratio ◽  
Area Under The Curve ◽  
Left Ventricular ◽  
Right Atrial ◽  
Risk Scores ◽  
External Assessment ◽  
Failure Risk

AbstractThe EUROMACS Right-Sided Heart Failure Risk Score was developed to predict right ventricular failure (RVF) after left ventricular assist device (LVAD) placement. The predictive ability of the EUROMACS score has not been tested in other cohorts. We performed a single center analysis of a continuous-flow (CF) LVAD cohort (n = 254) where we calculated EUROMACS risk scores and assessed for right ventricular heart failure after LVAD implantation. Thirty-nine percent of patients (100/254) had post-operative RVF, of which 9% (23/254) required prolonged inotropic support and 5% (12/254) required RVAD placement. For patients who developed RVF after LVAD implantation, there was a 45% increase in the hazards of death on LVAD support (HR 1.45, 95% CI 0.98–2.2, p = 0.066). Two variables in the EUROMACS score (Hemoglobin and Right Atrial Pressure to Pulmonary Capillary Wedge Pressure ratio) were not predictive of RVF in our cohort. Overall, the EUROMACS score had poor external discrimination in our cohort with area under the curve of 58% (95% CI 52–66%). Further work is necessary to enhance our ability to predict RVF after LVAD implantation.

scholarly journals Heart in Acromegaly: The Echocardiographic Characteristics of Patients Diagnosed with Acromegaly in Various Stages of the Disease

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Agata Popielarz-Grygalewicz ◽  
Jakub S. Gąsior ◽  
Aleksandra Konwicka ◽  
Paweł Grygalewicz ◽  
Maria Stelmachowska-Banaś ◽  
...  
Keyword(s):  
Right Ventricular ◽  
Healthy Volunteers ◽  
Global Longitudinal Strain ◽  
Interventricular Septum ◽  
Left Ventricular ◽  
Volume Index ◽  
Control Group ◽  
Glucose Metabolism Disorders ◽  
Acromegalic Cardiomyopathy ◽  
The Right

To determine whether the echocardiographic presentation allows for diagnosis of acromegalic cardiomyopathy. 140 patients with acromegaly underwent echocardiography as part of routine diagnostics. The results were compared with the control group comprising of 52 age- and sex-matched healthy volunteers. Patients with acromegaly presented with higher BMI, prevalence of arterial hypertension, and glucose metabolism disorders (i.e., diabetes and/or prediabetes). In patients with acromegaly, the following findings were detected: increased left atrial volume index, increased interventricular septum thickness, increased posterior wall thickness, and increased left ventricular mass index, accompanied by reduced diastolic function measured by the following parameters: E’med., E/E’, and E/A. Additionally, they presented with abnormal right ventricular systolic pressure. All patients had normal systolic function measured by ejection fraction. However, the values of global longitudinal strain were slightly lower in patients than in the control group; the difference was statistically significant. There were no statistically significant differences in the size of the right and left ventricle, thickness of the right ventricular free wall, and indexed diameter of the ascending aorta between patients with acromegaly and healthy volunteers. None of 140 patients presented systolic dysfunction, which is the last phase of the so-called acromegalic cardiomyopathy. Some abnormal echocardiographic parameters found in acromegalic patients may be caused by concomitant diseases and not elevated levels of GH or IGF-1 alone. The potential role of demographic parameters like age, sex, and/or BMI requires further research.

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