Practicality and Safety of Electrical Pulmonary Vein Isolation and Left Atrial Appendage Ligation in Lung Transplant Recipients With Pretransplant Atrial Fibrillation.

Background: Lung transplant surgery creates surgical pulmonary vein isolation (PVI) as a routine part of the procedure. However, many patients with pretransplant atrial fibrillation continue to have atrial fibrillation at 1 y. We hypothesized that the addition of electrical PVI and left atrial appendage isolation/ligation (LAL) to the lung transplant procedure restores sinus rhythm at 1 y in patients with pretransplant atrial fibrillation. Methods: We retrospectively reviewed all adult lung transplant recipients at the University of California Los Angeles from April 2006 to August 2021. All patients with pretransplant atrial fibrillation underwent concomitant PVI/LAL and were compared with lung transplant recipients without preoperative atrial fibrillation. In-hospital outcomes; 1-y survival; and the incidence of stroke, cardiac readmissions, repeat ablations, and sinus rhythm (composite endpoint) were examined at 1 y for the PVI/LAL cohort. Results: Sixty-one lung transplant recipients with pretransplant atrial fibrillation underwent concomitant PVI/LAL. No patient in the PVI/LAL cohort required cardiac-related readmission or catheter ablation for atrial fibrillation within 1 y of transplantation. Freedom from the composite endpoint of death, stroke, cardiac readmission, and repeat ablation for atrial fibrillation at 1 y was 85% (95% confidence interval, 73%-92%) for lung transplant recipients treated with PVI/LAL. Conclusions: The addition of PVI/LAI to the lung transplant operation in patients with pretransplant atrial fibrillation was safe and effective in maintaining sinus rhythm and baseline risk of stroke at 1 y.

Lung Transplantation from hepatitis C+ donor lungs: Reassuring midterm outcomes.

BACKGROUND: The development of modern antiviral therapy for hepatitis C virus (HCV) has allowed for the transplantation of HCV nucleic acid amplification testing-positive (NAT+) donor lungs with acceptable short-term outcomes. We sought to evaluate trends and midterm outcomes of lung transplant recipients of HCV NAT+ donor allografts. METHODS: All adults undergoing isolated lung transplantation in the United Network for Organ Sharing database from January 2016 to December 2022 were included in the study. Lung transplant recipients were stratified based on donor HCV status (HCV NAT+ vs NAT-). Propensity score matching was used to adjust for differences between groups. Several outcomes, including acute rejection by 1 year, early (30-day and in-hospital) mortality, and both 1- and 3-year survival, were compared between matched groups. RESULTS: A total of 16,725 patients underwent lung transplantation during the study period, with 489 (3%) receiving HCV NAT+ donor lungs. Regions 1 (18%) and 6/8 (both 0%) had the highest and lowest proportions, respectively, of HCV NAT+ donor transplants. Utilization of HCV NAT+ donors increased throughout the study period from 2 (0.1%) in 2016 to a peak of 117 (5%) in 2019. Donors who were HCV NAT+ were younger (34 vs 36 years, p < 0.001), more often female (44% vs 39%, p < 0.01), and more commonly died due to drug intoxication (56% vs 15%, p < 0.001). Recipients of HCV NAT+ donor lungs were similar in age (62 vs 62 years, p = 0.69) and female gender (43% vs 39%, p = 0.15) but had lower lung allocation scores (38 vs 41, p < 0.001) compared to others. Rates of acute rejection (13% vs 17%, p = 0.09), early mortality (30-day: 2% vs 1%, p = 0.59, in-hospital: 3% vs 4%, p = 0.38), as well as 1-year (90% vs 92%, p = 0.29) and 3-year survival (69% vs 75%, p = 0.13) were not significantly different between matched groups. CONCLUSIONS: Lung transplant recipients of HCV NAT+ donor allografts experience similar rates of acute rejection, early mortality, and 3-year survival compared to all other lung recipients. Increased use of HCV NAT+ donor allografts may help to expand the donor pool and alleviate donor shortages.

Safety and efficacy of delaying lung transplant surgery to a morning start.

Objective: We aimed to evaluate the safety and efficacy of delaying lung transplantation until morning for donors with cross-clamp times occurring after 1:30 am. Methods: All consented adult lung transplant recipients between March 2018 and May 2022 with donor cross-clamp times between 1:30 am and 5 am were enrolled prospectively in this study. Skin incision for enrolled recipients was delayed until 6:30 am (Night group). The control group was identified using a 1:2 logistic propensity score method and included recipients of donors with cross-clamp times occurring at any other time of day (Day group). Short- and medium-term outcomes were examined between groups. The primary endpoint was early mortality (30-day and in-hospital). Results: Thirty-four patients were enrolled in the Night group, along with 68 well-matched patients in the Day group. As expected, donors in the Night group had longer cold ischemia times compared to the Day group (344 minutes vs 285 minutes; P < .01). Thirty-day mortality (3% vs 3%; P = .99), grade 3 primary graft dysfunction at 72 hours (8% vs 4%; P = .40), postoperative complications (26% vs 38%; P = .28), and hospital length of stay (15 days vs 14 days; P = .91) were similar in the 2 groups. No significant differences were noted between groups in 3-year survival (70% vs 77%; P = .30) or freedom from chronic lung allograft dysfunction (91% vs 95%; P = .75) at 3 years post-transplantation. The median follow-up was 752.5 days (interquartile range, 487-1048 days). Conclusions: Lung transplant recipients with donor cross-clamp times scheduled after 1:30 am may safely have their operations delayed until 6:30 am with acceptable outcomes. Adoption of such a policy in clinically appropriate settings may lead to an alternative workflow and improved team well-being.

Anesthesia Considerations for Lead Extraction.

The role of the anesthesiologist in lead extraction procedures is multifaceted and highlights the collaborative, multidisciplinary teamwork needed to ensure patient safety and procedural success in these complex cases. Thorough preoperative evaluation and identification of high-risk characteristics enable the anesthesiologist to tailor a comprehensive intraoperative and postoperative care plan for each case. Institutional practices may vary but anesthetic management typically includes general anesthesia with an endotracheal tube, invasive measurement of arterial blood pressure, vascular access for rapid volume expansion, echocardiographic monitoring, preparation for blood transfusion, and initiation of cardiopulmonary bypass in the event of an emergency.

Changes in myocardial deformation after transcatheter and surgical aortic valve replacement.

Speckle tracking echocardiography (STE) has emerged as a novel angle-independent modality in assessing myocardial velocity, deformation, and strain. Its role in assessing change before and after aortic valve replacement in patients with aortic stenosis (AS) has recently generated interest. This review summarizes the practical utility and clinical implications of myocardial deformation by STE after surgical or transcatheter aortic valve replacement (TAVR). Overall, atrial strain and ventricular strain as measured by STE improve after surgical and transcatheter aortic intervention in short- and long-term follow-up with evidence of a more pronounced acute improvement in patients who undergo TAVR. STE assessment of strain, particularly global longitudinal strain, can detect subtle changes in myocardial systolic function prior to conventional variables such as left ventricular ejection fraction and is clinically useful in predicting mortality and symptom development in patients with AS. This underscores the emerging role of STE in monitoring post-procedural improvements in cardiac function as well as the potential value in guiding optimal timing of AS intervention.

Preoperative Three-Dimensional Strain Imaging Identifies Reduction in Left Ventricular Function and Predicts Outcomes After Cardiac Surgery.

BACKGROUND: Echocardiography-based speckle-tracking strain imaging is an emerging modality to assess left ventricular function. The aim of this study was to investigate the change in left ventricular systolic function after cardiac surgery with 3-dimensional (3D) speckle-tracking strain imaging and to determine whether preoperative 3D strain is an independent predictor of acute and long-term clinical outcomes after aortic valve, mitral valve, and coronary artery bypass grafting operations. METHODS: In total, 163 adult patients undergoing aortic valve, mitral valve, and coronary artery bypass surgeries were enrolled prospectively and had complete data sets. Demographic, operative, and outcome data were collected. 3D transthoracic echocardiograms were preformed preoperatively and on second to fourth postoperative day. Blinded off-line analysis was performed for left ventricular 2-dimensional (2D) ejection fraction (EF2D) and 3D ejection fraction (EF3D) and global peak systolic area, longitudinal, circumferential, and radial strain. RESULTS: 3D global strain correlated well with EF3D. Ventricular function as measured by strain imaging decreased significantly after all types of cardiac surgery. When preoperative EF3D was used, receiver operating characteristic curves identified reference values for 3D global strain corresponding to normal, mildly reduced, and severely reduced ventricular function. Normal ventricular function (EF3D ≥ 50%) corresponded to 3D global area strain -25%, with area under curve = 0.86 (0.81-0.89). Patients with reduced preoperative 3D global area strain had worse postoperative outcomes, including length of intensive care unit stay (4 vs 3 days, P = .001), major adverse events (27% vs 11%, P = .03), and decreased 1-year event-free survival (69% vs 88%, P = .005). After we controlled for baseline preoperative risk models including European System for Cardiac Operative Risk Evaluation score and surgery type, preoperative strain was an independent predictor of both short- and long-term outcomes, including length of intensive care unit stay, postoperative inotrope score, and 1-year event-free survival. CONCLUSIONS: This study shows that cardiac surgery was associated with an acute reduction in postoperative left ventricular function, when evaluated with 3D strain imaging. In addition, preoperative 3D strain was demonstrated to be an independent predictor of acute and long-term clinical outcomes after cardiac surgery. The use of noninvasive 3D transthoracic echocardiogram strain imaging before cardiac surgery may provide added information to aid in perioperative risk stratification and management for these high-risk patients.

Acute Effects of Pacing at Different Ventricular Sites on Left Ventricular Rotational Mechanics in a Porcine Model.

OBJECTIVE: The purpose of this study was to examine the acute effects of pacing at different ventricular sites on hemodynamics and left ventricular (LV) rotational mechanics using speckle-tracking echocardiography (STE) in a porcine model. DESIGN: A prospective laboratory investigation. SETTING: University research laboratory. PARTICIPANTS: Yorkshire pigs. INTERVENTIONS: In 9 pigs, after midline sternotomy, epicardial pacing was performed from the right ventricular outflow tract (RVOT), right ventricular apex (RVA), and LV free wall. MEASUREMENTS AND MAIN RESULTS: Two-dimensional STE and conductance catheter-derived LV pressure-volume measurements were made to determine the impact of pacing from various sites on LV rotational parameters (twist/untwist) and hemodynamics. RVOT pacing caused the least decrease in end-systolic pressure from baseline (-9.5%), when compared with RVA (-19.1%) and LV (-23.4%). Systolic and diastolic parameters (Emax, Tau) also were different among RVOT (4.7±0.8 mmHg/mL, 32±4 ms), RVA (3.9±0.7 mmHg/mL, 37±6 ms), and LV sites (3.6±0.8 mmHg/mL, 42±7 ms). Similar to the effects of pacing on hemodynamics, RVOT pacing better preserved LV twist (11.1±1.8 v 8.6±1.7, 5.9±0.7 °) and untwisting rate (64.6±8.5 v 56.2±5.3, 48.2±8.5 °/s) when compared with RV apical pacing and LV pacing. Furthermore, prolongation of conduction from LV lateral to anteroseptal at LV base (26.5±3.8 v 13.8±3.3 ms, p<0.05) and LV midpapillary muscle level (35.6±5.6 v 14.1±2.4 ms, p<0.05) was observed with LV pacing compared with RVOT pacing. CONCLUSIONS: The present data showed that the LV twist/untwist and cardiac systolic and diastolic function were least affected by RVOT pacing. This finding may be explained by the proximity of this location to the native ventricular conduction system.

Salvage of infected left ventricular assist device with antibiotic beads.

BACKGROUND: The use of left ventricular assist devices has become common for the treatment of end-stage heart failure, both as a bridge to transplantation and as destination therapy. The nature of these devices and the comorbid conditions of the patients in whom the devices are implanted lead to high rates of device infection that are related directly to mortality. METHODS: Over 2 years, the senior author (S.A.I.) treated 26 patients with left ventricular assist device infections, ranging from superficial driveline infections to deeper pocket infections and device infections. An algorithm involving the use of repeated débridement and placement of antibiotic beads was used in treatment of these infections. Once cleared of infection, patients were treated with definitive closure or flap coverage of the formerly infected device component. RESULTS: Seventeen of 26 patients with left ventricular assist device-related infections were cleared of their infection using this method. Ten of these patients underwent flap coverage of the device after their infection was cleared. In patients that were cleared of infection, mortality was 29 percent, whereas patients with recalcitrant infections had a mortality of 67 percent over the course of the study. CONCLUSIONS: A systematic approach to treating left ventricular assist device-related infections has the potential to treat and clear these infections, with promising overall survival rates. This proposed algorithm led to high infection clearance rates compared with previously published literature. Infection clearance in patients on left ventricular assist device destination therapy may result in mortality rates approaching those of their uninfected peers.

Acute right ventricular pressure overload compromises left ventricular function by altering septal strain and rotation.

While right ventricular (RV) dysfunction has long been known to affect the performance of left ventricle (LV), the mechanisms remain poorly defined. Recently, speckle-tracking echocardiography has demonstrated that preservation of strain and rotational dynamics is crucial to both LV systolic and diastolic function. We hypothesized that alteration in septal strain and rotational dynamics of the LV occurs during acute RV pressure overload (RVPO) and leads to decreased cardiac performance. Seven anesthetized pigs underwent median sternotomy and placement of intraventricular pressure-volume conductance catheters. Two-dimensional echocardiographic images and LV pressure-volume loops were acquired for offline analysis at baseline and after banding of the pulmonary artery to achieve RVPO (>50 mmHg) induced RV dysfunction. RVPO resulted in a significant decrease (P < 0.05) in LV end-systolic elastance (50%), systolic change in pressure over change in time (19%), end-diastolic volume (22%), and cardiac output (37%) that correlated with decrease in LV global circumferential strain (58%), LV apical rotation (28%), peak untwisting (reverse rotation) rate (27%), and prolonged time to peak rotation (17%), while basal rotation was not significantly altered. RVPO reduced septal radial and circumferential strain, while no other segment of the LV midpapillary wall was affected. RVPO decreased septal radial strain on LV side by 27% and induced a negative radial strain from 28 ± 5 to -16 ± 2% on the RV side of the septum. The septal circumferential strain on both LV and RV side decreased by 46 and 50%, respectively, following RVPO (P < 0.05). Our results suggest that acute RVPO impairs LV performance by primarily altering septal strain and apical rotation.

Effect of pharmacologic increases in afterload on left ventricular rotation and strain in a rabbit model.

BACKGROUND: Assessment of left ventricular rotational mechanics and myocardial deformation may provide new insight into both systolic and diastolic function. However, the effects of increasing afterload on these measures of cardiac function are poorly understood. The aim of this study was to identify the changes in left ventricular function and rotational mechanics during increasing pharmacologic afterload. METHODS: In 14 anesthetized rabbits, two-dimensional speckle-tracking echocardiographic images and left ventricular pressure-volume loops were acquired at baseline and during norepinephrine, phenylephrine, and vasopressin infusion at increasing doses. Maximal ventricular elastance, arterial elastance, ventricular-arterial coupling, dP/dt, the time constant of relaxation, and other hemodynamic parameters were determined. RESULTS: An increase in dP/dtmax with norepinephrine and phenylephrine and a decrease with vasopressin at escalating doses were detected. Ventricular-arterial coupling was preserved with norepinephrine and phenylephrine but decreased with vasopressin (P < .05). Apical rotation, rotational rate, and strain were preserved during the norepinephrine and phenylephrine infusions but were reduced with vasopressin (P < .05). Apical rotation and circumferential strain were significantly correlated with both ventricular-arterial coupling (r = 0.84 and r = 0.81) and dP/dtmax (r = -0.81 and r = -0.77). High-dose vasopressin decreased the diastolic time constant of relaxation and dP/dtmin while reducing apical untwisting rate. CONCLUSIONS: Pharmacologic increases in afterload with vasopressin resulted in greater derangements in ventricular-arterial coupling and cardiac performance compared with norepinephrine and phenylephrine. Rotation and strain correlated well with invasively determined measures and can be used to assess afterload-induced alteration in cardiac function.

Effectiveness of using the front door score to enhance the chest pain triage accuracy of emergency nurse triage decisions.

BACKGROUND: Nurses lack a standard tool to stratify the risk of chest pain in triage patients. The type of risk stratification may correspond to the type of acuity rating of the 5-level triage scale adopted by nurses for chest pain triage, based on the Front Door Score, simplified from the Thrombolysis in Myocardial Infarction Risk Score for unstable angina or non-ST-segment elevation myocardial infarction. AIM: This study aimed to evaluate the ability of using the Front Door Score to enhance the accuracy of emergency nurse triage decisions for patients who present with chest pain. DESIGN: A cross-sectional descriptive design was used. METHODS: A convenience sample of 200 subjects was obtained from an emergency department in Hong Kong. Data were collected via a questionnaire. The final physician diagnoses were used as the gold standard in justifying the appropriateness of the risk stratification of chest pain. The agreement rates among the final physician diagnoses, Thrombolysis in Myocardial Infarction Risk Score for unstable angina or non-ST-segment elevation myocardial infarction, nurses using the triage scale, and nurses using the Front Door Score were computed using κ statistics. RESULTS: A significant substantial agreement was observed between the final physician diagnoses and nurses using the Front Door Score. In comparison, the agreement between the final physician diagnoses and nurses using the triage scale was poor. CONCLUSION: The chest pain triage reliability of nurses using the Front Door Score was found to be much more credible than that of nurses using the triage scale. A suggested conversion of the scales of Front Door Score was established. CLINICAL IMPLICATIONS: The Front Door Score should be considered as a standard tool to enhance the chest pain triage accuracy of emergency nurse triage decisions.

Transthoracic echocardiography simulation is an efficient method to train anesthesiologists in basic transthoracic echocardiography skills.

BACKGROUND: The clinical utility of focused transthoracic echocardiography (TTE) is increasingly recognized in perioperative medicine. However its use is limited among anesthesiologists because of a lack of training. The most efficient training methods have not been determined. We hypothesized that simulation-based TTE training would be more effective than traditional lecture-based methods for teaching basic TTE skills to the anesthesiology residents. METHODS: In this prospective randomized study, 61 anesthesiology residents (in anesthesia clinical training years 1 to 3) were randomized to either control (n = 30) or simulation groups (n = 31) for TTE training. A standardized pretest was administered before TTE training sessions of 45 minutes each. The first training session used a lecture-based video didactic in the control group or a TTE simulator in the simulation group. Comprehension in both groups was then assessed using a written posttest and by performing a TTE examination on a volunteer subject. TTE examinations were graded on the ability to acquire the correct image, image quality, anatomy identification, and time required to attain proper imaging by 2 blinded experts. A second training session incorporating "hands-on" training with a volunteer subject was conducted in a subset of 21 residents (n = 11 control, n = 10 simulation). The simulation group included additional simulator training. After the second session, another posttest on a volunteer subject was administered. RESULTS: Pretest scores revealed similar preintervention knowledge among residents (56.0% ± 11.9% vs 59.3% ± 11.0%, P = 0.25; control versus simulator group, respectively). The simulation group scored higher on all criteria after the first training session: written posttest (57.9% ± 8.8% vs 68.2% ± 10.1%; P < 0.001), volunteer subject posttest image quality scores (0 to 25 scale) (6.4 ± 3.5 vs 12.4 ± 4.2; P = 0.003), anatomy identification scores (0 to 25 scale) (8.3 ± 6.6 vs 17.8 ± 6.6; P = 0.003), and percentage correct views (50 ± 19 vs 78 ± 21; P < 0.001). After the second session, all scores were again improved in the simulation group: volunteer subject posttest image quality scores (9.6 ± 3.3 vs 15.6 ± 2.8; P = 0.002), anatomy identification scores: (17.6 ± 3.8 vs 22.8 2.4; P = 0.003), and percentage correct views (80 ± 16 vs 96 ± 8; P = 0.007). DISCUSSION: This prospective randomized study demonstrated that anesthesiology residents trained with simulation acquired better skills in TTE image acquisition and anatomy identification on volunteer subjects. The educational benefit of simulation persisted even with introduction of hands-on instruction with volunteer subjects in both groups. The impact of these short-term educational approaches on longer-term retention and actual clinical application warrants further investigation.

Adenocarcinoma of the parotid gland metastatic to the ventricular septum and right ventricular wall.

Adenocarcinoma of the parotid gland metastatic to the right ventricle has rarely been reported in the medical literature. We describe the case of a 51-year-old man who had a right ventricular adenocarcinoma that metastasized from his right parotid gland. He had undergone incomplete resection of the parotid tumor, followed by radiotherapy, 5 years earlier. After resecting the cardiac adenocarcinoma with tumor-free margins, we reconstructed the ventricular septum and right ventricle, then performed coronary artery bypass grafting. At the patient's most recent follow-up examination 6 months later, he continued to do well and had a good quality of life.

Prolonged central venous desaturation measured by continuous oximetry is associated with adverse outcomes in pediatric cardiac surgery.

BACKGROUND: The role of continuous central venous oxygen saturation (ScvO2) oximetry during pediatric cardiac surgery for predicting adverse outcomes is not known. Using a recently available continuous ScvO2 oximetry catheter, we examined the association between venous oxygen desaturations and patient outcomes. We hypothesized that central venous oxygen desaturations are associated with adverse clinical outcomes. METHODS: Fifty-four pediatric patients undergoing cardiac surgery were prospectively enrolled in an unblinded observational study. ScvO2 was measured continuously in the operating room and for up to 24 h post-Intensive Care Unit admission. The relationships between ScvO2 desaturations, clinical outcomes, and major adverse events were determined. RESULTS: More than 18 min of venous saturations less than 40% were associated with major adverse events with 100% sensitivity and 97.6% specificity. Significant correlations resulted between the ScvO2 area under the curve less than 40% and creatinine clearance at 12 h in the Intensive Care Unit (r = -0.58), Intensive Care Unit length of stay (r = 0.56), max inotrope use (r = 0.52), inotrope use at 24 h (r = 0.40), inotrope index score (r = 0.39), hospital length of stay (r = 0.36), and length of intubation (r = 0.32). CONCLUSIONS: We demonstrate that ScvO2 desaturations by continuous oximetry are associated with major adverse events in pediatric patients undergoing cardiac surgery. The most significant associations with major adverse events are seen in patients with greater than 18 min of central venous saturations less than 40%. Our results support the further investigation of ScvO2 as a potential target parameter in high-risk pediatric patients to minimize the risk of major adverse events.

Incidental intracardiac thromboemboli during liver transplantation: incidence, risk factors, and management.

Even though numerous cases of massive thromboemboli have been reported in the literature, intracardiac thromboemboli (ICTs) incidentally found during orthotopic liver transplantation (OLT) have not been examined. In this study, we retrospectively examined the incidence, risk factors, and management of incidental ICTs during OLT. After institutional review board approval, adult patients who underwent OLT between January 2004 and December 2008 at our center were reviewed. ICTs were identified and confirmed by the examination of OLT datasheets, anesthesia records, and recorded transesophageal echocardiography (TEE) clips. The clinical presentation, management, and outcomes of the patients with ICTs were reviewed. Risk factors were analyzed by multivariate logistic regression. During the study period, 426 of the 936 adult OLT patients (45.5%) underwent intraoperative TEE monitoring. Incidental ICTs were identified in 8 of these 426 patients (1.9%). Two ICTs occurred before reperfusion, and 6 ICTs occurred after reperfusion. The treatment was at the discretion of the treating physicians; however, none of the patients received an anticoagulant or thrombolytics. Multivariate analysis identified 2 independent risk factors for intraoperative incidental ICTs: the presence of symptomatic or surgically treated portal hypertension (a history of gastrointestinal bleeding, a transjugular intrahepatic portosystemic shunt procedure, or portocaval shunt surgery) before OLT and intraoperative hemodialysis (odds ratios of 4.05 and 7.29, respectively; P < 0.05 for both). In conclusion, incidental ICTs during OLT occurred at a rate of 1.9% and were associated with several preoperative and intraoperative risk factors. The use of TEE allows early identification, which may be important. Our management for incidental ICTs is described; however, no conclusions can be made about the optimal therapy.

Cardiac resynchronization therapy for treatment of heart failure.

Conduction abnormalities, commonly seen in systolic heart failure, lead to delayed activation of the myocardium as the electrical impulse spreads slowly without the aid of healthy conduction tissue. The resulting dyssynchronous ventricular contraction is mechanically less efficient, reducing systolic function and impairing diastolic filling. Simultaneous pacing of the right and left ventricles (i.e., biventricular pacing) reduces ventricular dyssynchronous contraction, overcoming these consequences of conduction delay. An important role for implantable rhythm-management devices providing cardiac resynchronization therapy has emerged in the optimization of ventricular function in heart failure. Long-term benefits in patient outcomes have been well established. With increasing use, understanding of cardiac resynchronization therapy devices and the principles behind the therapy are important for physicians providing perioperative and intensive care for patients with heart failure.

Right ventricular failure resulting from pressure overload: role of intra-aortic balloon counterpulsation and vasopressor therapy.

BACKGROUND: Augmentation of coronary perfusion may improve right ventricular (RV) failure following acute increases of RV afterload. We investigated whether intra-aortic balloon counterpulsation (IABP) can improve cardiac function by enhancing myocardial perfusion and reversing compromised biventricular interactions using a model of acute pressure overload. MATERIALS AND METHODS: In 10 anesthetized pigs, RV failure was induced by pulmonary artery constriction and systemic hypertension strategies with IABP, phenylephrine (PE), or the combination of both were tested. Systemic and ventricular hemodynamics [cardiac index(CI), ventricular pressures, coronary driving pressures (CDP)] were measured and echocardiography was used to assess tricuspid valve regurgitation, septal positioning (eccentricity index (ECI)), and changes in ventricular and septal dimensions and function [myocardial performance index (MPI), peak longitudinal strain]. RESULTS: Pulmonary artery constriction resulted in doubling of RV systolic pressure (54 ± 4mm Hg), RV distension, severe TR (4+) with decreased RV function (strain: -33%; MPI: +56%), septal flattening (Wt%: -35%) and leftward septal shift (ECI:1.36), resulting in global hemodynamic deterioration (CI: -51%; SvO(2): -26%), and impaired CDP (-30%; P<0.05). IABP support alone failed to improve RV function despite higher CDP (+33%; P<0.05). Systemic hypertension by PE improved CDP (+70%), RV function (strain: +22%; MPI: -21%), septal positioning (ECI:1.12) and minimized TR, but LV dysfunction (strain: -25%; MPI: +31%) occurred after LV afterloading (P<0.05). With IABP, less PE (-41%) was needed to maintain hypertension and CDP was further augmented (+25%). IABP resulted in LV unloading and restored LV function, and increased CI (+46%) and SvO(2) (+29%; P<0.05). CONCLUSIONS: IABP with minimal vasopressors augments myocardial perfusion pressure and optimizes RV function after pressure-induced failure.