Prognostic significance of persistent right ventricular dysfunction as assessed by radionuclide angiocardiography in patients with inferior wall acute myocardial infarction

Right Ventricular Myocardial Infarctions

Acute isolated right ventricular (RV) myocardial infarctions are relatively uncommon in clinical practice; more frequently, RV infarctions occur in association with inferior ST-segment elevation myocardial infarctions. Recent advances in diagnostic tools and methods have significantly improved our ability to detect RV infarctions in both scenarios. For this reason, it is critical for physicians to understand the pathophysiology, clinical presentation, and diagnostic criteria for RV infarctions to initiate treatment and optimize the outcomes of patients. About half of all patients with an inferior ST-segment elevation myocardial infarction develop RV infarction. In the acute setting, RV infarctions can lead to hemodynamic instability and frank shock, which are responsible for the high morbidity and mortality associated with these episodes. However, when treated properly, the prognosis of RV myocardial infarctions is quite excellent if the patient survives the acute hemodynamic compromise. In addition, RV infarctions are likely a misnomer since these events tend to represent ischemia and stunning of the RV myocardium that results in its short-term dysfunction, but the myocardium remains viable and recovers over time with no signs of an infarct if the patient survives the episode. In fact, patient outcomes in RV ischemia are dependent more on the involvement of the left ventricle than RV involvement, especially since a left ventricular infarct and dysfunction can be difficult to overcome in the long term. It is imperative to understand the various treatments available to target the hemodynamic changes and shock often seen in patients with acute RV ischemia and to implement these treatments accordingly to improve patient survival and prognosis.

Management of Post-Myocardial Infarction Right Ventricular Failure

Right ventricular failure (RVF) due to an acute myocardial infarction (MI) has been associated with high morbidity and mortality. Initial treatment is guided by early recognition and prompt revascularization. Current management of post-MI RVF is built upon expert consensus and is also informed by RVF from other etiologies, including massive pulmonary embolism, left ventricular assist device-associated right ventricular dysfunction, postcardiotomy shock, etc.; this speaks to the limited data available on the specific management of RVF in acute MI. The goal of this review is to discuss the current literature on the pathophysiology, general management considerations, interventional management, hemodynamic monitoring, medical management, and mechanical circulatory support of MI-induced RVF.

Heart Failure After Right Ventricular Myocardial Infarction

PURPOSE OF REVIEW

Heart failure (HF) after right ventricular myocardial infarction (RVMI) is common and complicates its clinical course. This review aims to provide a current overview on the characteristic features of RV failure with focus on acute management.

RECENT FINDINGS

While HF after RVMI is classically seen after acute proximal right coronary artery occlusion, RV dysfunction may also occur after larger infarctions in the left coronary artery. Because of its different anatomy and physiology, the RV appears to be more resistant to permanent infarction compared to the LV with greater potential for recovery of ischemic myocardium. Hypotension and elevated jugular pressure in the presence of clear lung fields are hallmark signs of RV failure and should prompt confirmation by echocardiography. Management decisions are still mainly based on small studies and extrapolation of findings from LV failure. Early revascularization improves short- and long-term outcomes. Acute management should further focus on optimization of preload and afterload, maintenance of sufficient perfusion pressures, and prompt management of arrhythmias and concomitant LV failure, if present. In case of cardiogenic shock, use of vasopressors and/or inotropes should be considered along with timely use of mechanical circulatory support (MCS) in eligible patients. HF after RVMI is still a marker of worse outcome in acute coronary syndrome. Prompt revascularization, careful medical therapy with attention to the special physiology of the RV, and selected use of MCS provide the RV the time it needs to recover from the ischemic insult.

Role of N-terminal pro-B-type natriuretic peptide and troponin T in predicting right ventricular recovery in myocardial infarction

OBJECTIVES

The determinants of right ventricular (RV) recovery after successful revascularization in ST-elevation myocardial infarction (STEMI) patients are not clear. Besides, the relationship between Troponin T (TnT), N-terminal pro-B-type natriuretic peptide (NT-proBNP) and improvement in RV function is also unknown. This study hypothesizes that a lower TnT and NT-proBNP level would be associated with RV recovery.

METHODS

One hundred forty-eight STEMI patients were included in our study. Echocardiography were performed before and 12-18 weeks after discharge. Patients were divided into three groups according to the changes in tricuspid annular plane systolic excursion (TAPSE) as 53 patients with ≥10% change, 41 patients with 1-9% change, and 54 patients ≤0% change. RV recovery was accepted as ≥10% TAPSE improvement and the predictors of RV recovery were investigated.

RESULTS

RV recovery was detected in 35.8% of the patients. Low baseline left ventricular ejection fraction (OR: 0.91 [0.84-0.98], p=0.023), NT-proBNP (OR: 0.93 [0.89-0.98], p=0.014), TnT (OR: 0.84 [0.68-0.93], p=0.038), inferior myocardial infarction (OR: 2.66 [1.10-6.40], p=0.028), wall motion score index ratio (OR: 0.93 [0.88-0.97], p=0.002) and post-percutaneous coronary intervention TIMI flow 3 (OR: 5.84 [1.41-24.22], p=0.015) were determined as independent predictors of RV recovery. Being in the high TnT group 4.2 times, and being in the high NT-proBNP group 5.3 times could predict the failure to achieve RV recovery. Furthermore, when high TnT level was combined with high NT-proBNP level, the odds ratio of failure to achieve RV recovery was the highest (OR: 8.03 [2.59-24.89], p<0.001).

CONCLUSIONS

Lower TnT and lower NT-proBNP level was associated with better improvement in RV function in STEMI patients.

Right ventricular dysfunction and long-term risk of death

Sudden cardiac death (SCD), or sudden loss of life-sustaining systemic and cerebral perfusion, is most often due to left ventricular (LV) dysfunction secondary to ischemic or structural cardiac disease or channelopathies. Degeneration of sinus rhythm into ventricular tachycardia and ultimately ventricular fibrillation is the final common pathway for most heart failure patients. Right ventricular (RV) dysfunction is recognized as an independent contributor to worsening heart failure. There is emerging evidence that RV dysfunction may also be an independent predictor of SCD. This review examines the role of RV dysfunction on modifying long term risk of SCD, and explores possible mechanisms that may underlie SCD. The RV has unique anatomy and physiology compared to the LV. Subsequently, we begin with a review of cardiac embryology, focusing on the chambers, valves, coronary arteries, and cardiac conduction system to understand the origins of RV dysfunction. Static and dynamic physiology of the RV is contrasted with that of the LV. Particular emphasis is placed on ventriculo-arterial coupling, mechanical cardiac constraint, and ventricular interdependence. The epidemiology of SCD is briefly reviewed to highlight how causes of SCD are age-specific. In turn, the age-specific causes of RV dysfunction are presented, including those which predominate in childhood and adolescence [arrhythmogenic RV dysplasia (ARVD) and hypertrophic cardiomyopathy (HCM)] and older adulthood (cardiac ischemia, chronic congestive heart failure and post-capillary pulmonary hypertension, and pulmonary hypertension). There is a clear need for additional studies on the independent contribution of RV dysfunction to overall functional capacity, SCD-associated mortality, and non-SCD-associated mortality. Discovery would be aided by the development of prospective cohorts with excellent RV phenotyping, coupled with deeper biologic measurements linking mechanisms to clinically relevant outcomes.

Right Ventricular Dysfunction in Right Coronary Artery Infarction: A Primary PCI Registry Analysis

Right ventricular involvement in inferior myocardial infarction (MI) was historically associated with a poor prognosis. However, few studies addressed the impact of right ventricular (RV) dysfunction in the primary percutaneous intervention (pPCI) era. Our aim was to assess the prognostic significance of RV dysfunction in right coronary artery (RCA) related MI treated with pPCI.

METHODS

A total of 298 patients with a RCA related MI undergone pPCI between January 2011 and June 2015 were included. RV dysfunction was defined by a RV-FAC <35% at echocardiographic examination and further divided into mild (RV-FAC between 35 and 25%) and moderate-severe (RV-FAC <25%). RV function before discharge was reassessed in 95% of the study cohort. The primary endpoint was overall mortality. Median follow-up was 29 months.

RESULTS

In RCA related MI, moderate-severe (HR 5.882, p = 0.002, 95% CI 1.882-18.385) but not mild RV dysfunction independently predicted lower survival at follow-up along with age (HR 1.104, p <0.001, CI 1.045-1.167). Importantly, patients recovering RV function at discharge showed a lower mortality (p = 0.001) vs patients with persistent moderate-severe RV dysfunction) that approached the risk of patients without RV dysfunction at presentation.

CONCLUSION

In RCA related MI treated with pPCI, RV dysfunction was one of the strongest independent predictor of lower overall survival. However, patients with only transient RV dysfunction showed a better prognosis compared to patients who had persistent RV dysfunction. The focus on intensive support management of the RV in the first hours after pPCI may be important to overcome the acute phase and to promote RV recovery.

Elevated 1-h post-load plasma glucose is associated with right ventricular morphofunctional parameters in hypertensive patients

PURPOSE

Emerging data demonstrate that type 2 diabetes mellitus (T2DM) is associated with right ventricular (RV) dysfunction. A cutoff point of 155 mg/dL for the 1-hour (h) post-load plasma glucose, during oral glucose tolerance test (OGTT), identifies patients with normal glucose tolerance (NGT) at high risk to develop T2DM and cardiovascular (CV) disease. We investigated if 1-h post-load glucose may affect RV geometry and function in a group of never-treated hypertensive individuals.

METHODS

We enrolled 446 Caucasian newly diagnosed hypertensive outpatients. All patients underwent an OGTT and a standard echocardiography. The tricuspid annular plane systolic excursion (TAPSE) and the RV fractional area change (RVFAC) were measured together with systolic pulmonary arterial pressure (s-PAP) and pulmonary vascular resistances (PVR). Insulin sensitivity was evaluated using the Matsuda index.

RESULTS

Among all partecipants, 296 had NGT, 100 impaired glucose tolerance (IGT), and 50 T2DM. Considering the cutoff point of 155 mg/dl for 1-h glucose, NGT subjects were stratified into two groups: NGT < 155 (n = 207), NGT ≥ 155 (n = 89). Subjects NGT ≥ 155 presented a worse metabolic and inflammatory profile than NGT < 155. RV functional parameters (TAPSE, RVFAC, TAPSE/s-PAP, and TAPSE/PVR) were significantly reduced in NGT ≥ 155 subjects compared with NGT < 155 patients. On the contrary, s-PAP and PVR were significantly higher. At multiple regression analysis, 1-h glucose was the strongest predictor of TAPSE in NGT ≥ 155, IGT, and T2DM.

CONCLUSIONS

The presence of RV impairment in hypertensive NGT ≥ 155 subjects further complicates their CV burden and it may, at least in part, justify the worse clinical outcome in this setting of patients.

Can 3D RVEF be Prognostic for the Non-Ischemic Cardiomyopathy Patient but not the Ischemic Cardiomyopathy Patient? A Cardiovascular MRI Study

Background: While left ventricular ejection fraction (LVEF) has been shown to have prognostic value in ischemic cardiomyopathy (ICMX) patients, right ventricular ejection fraction (RVEF) has not been systematically evaluated in either ICMX or non-ischemic cardiomyopathy (NICMX) patients. Moreover, an accurate estimation of RVEF is problematic due to the geometry of the right ventricle (RV). Over the years, there have been improvements in the resolution, image acquisition and post-processing software for cardiac magnetic resonance imaging (CMR), such that CMR has become the “gold standard” for measuring RV volumetrics and RVEF. We hypothesize that CMR defines RVEF more so than LVEF and might have prognostic capabilities in ischemic and non-ischemic cardiomyopathy patients (ICMX and NICMX). Methods: Patients that underwent CMR at our institution between January 2005 and October 2012 were retrospectively selected if three-dimensional (3D) LVEF < 35%. Patients were further divided into ICMX and NICMX groups. The electronic medical record (EMR) database inquiry determined all-cause mortality and major adverse cardiovascular events (MACE). Additionally, a Social Security Death Index (SSI) database inquiry was performed to determine all-cause mortality in patients who were lost to follow-up. Patients were further sub-grouped on the basis of 3D RVEF ≥ 20%. Separately, patients were sub-grouped by LVEF ≥ 20% in both ICMX and NICMX cases. A cut-off of ≥20% was chosen for the RVEF based on the results of prior studies showing significance based on Kaplan–Meier (KM) survival curves. Cumulative event rates were estimated for each subgroup using the KM analysis and were compared using the log-rank test. The 3D RV/LVEFs were compared to all-cause mortality and MACE. ICMX patients were defined using the World Health Organization (WHO) criteria. Results: From a 7000-patient CMR database, 753 heart failure patients were selected. Eighty-seven patients met WHO definition of ICMX and NICMX (43 ICMX and 44 NICMX). The study patients were followed for a median of 3 years (Interquartile range or IQR 1.5–6.5 years). The mean age of patients was 58 ± 13 years; 79% were male. In ICMX, mean 3D LVEF was 21% ± 6% and mean 3D RVEF was 38% ± 14%, while for NICMX, mean 3D LVEF was 16% ± 6% and mean 3D RVEF was 30% ± 14% (p < 0.005 for intra- and inter-group comparison). It should be noted that LVEF < RVEF in both groups and the ejection fraction (EF) in NICMX was less than the corresponding EF in ICMX. Overall mortality was higher in ICMX than NICMX (12/40, 30% vs. 7/43, 16%; p < 0.05). Patients were stratified based on both RVEF and LVEF with a threshold of EF ≥ 20% separately. RVEF but not LVEF was a significant predictor of death for NICMX (χ² = 8; p < 0.005), while LVEF did not predict death in ICMX (χ² = 2, p = not significant). Similarly, time to MACE was predicted by RVEF for NICMX (χ² = 9; p < 0.005) but not by LVEF in ICMX (χ² = 1; p = NS). Importantly, RVEF, while predictive of NICMX MACE, did not emerge as a predictor of survival or MACE in ICMX. Conclusions: Via 3D CMR in non-ischemic CMX patients, RVEF has important value in predicting death and time to first MACE while 3D LVEF is far less predictive.

Determinants of right ventricular remodeling following ST-segment elevation myocardial infarction

Right ventricular (RV) function after ST-segment elevation myocardial infarction (STEMI) has important prognostic implications. However, the changes in RV function over time after STEMI and the incidence of RV remodeling remain unknown. The present study evaluated changes in RV dimensions and function in contemporary patients with first STEMI and assessed the independent determinants of RV dysfunction at follow-up. Patients with first STEMI (n = 940, 60 ± 11 years, 77% men) treated with primary percutaneous coronary intervention underwent echocardiography at baseline and 6- and 12-month follow-up. The prevalence of RV dysfunction (tricuspid annular plane systolic excursion [TAPSE] ≤15 mm) decreased significantly at 6 months follow-up (from 15% to 8%, p <0.001) and the incidence of RV remodeling (increase in RV end-diastolic area [RVEDA] ≥20%) was observed in 200 patients (25%). Absolute changes in RVEDA were independently associated with absolute changes in wall motion score index and left ventricular (LV) remodeling (p <0.001 for both parameters), whereas absolute changes in TAPSE were independently related with absolute changes in wall motion score index and mitral regurgitation grade (p <0.001 for both parameters). Independent correlates of RV dysfunction at 6 months follow-up were multivessel coronary disease (odds ratio [OR] 2.13), peak cardiac troponin T (OR 1.05), angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers use (OR 0.27), baseline LV ejection fraction (OR 0.96) and baseline TAPSE (OR 0.88). In conclusion, despite the non-negligible incidence of RV remodeling in patients with first STEMI, RV function improves early after STEMI. Multivessel coronary disease, infarct size, baseline LV ejection fraction and TAPSE and the nonuse of angiotensin-converting enzyme inhibitors and/or angiotensin receptor blockers are independent determinants of RV dysfunction.

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

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.

Echocardiographic parameters as predictors of in-hospital mortality in patients with acute coronary syndrome undergoing percutaneous coronary intervention

Different ways have been used to stratify risk in acute coronary syndrome (ACS) patients. The aim of the study was to examine the usefulness of echocardiographic parameters as predictors of in-hospital outcome in patients with ACS after percutaneous coronary intervention (PCI). A data of 2030 patients with diagnosis of ACS hospitalized from December 2008 to December 2011 was used to develop a risk model based on echocardiographic parameters using the binary logistic regression. This model was independently evaluated in validation cohort prospectively (954 patients admitted during 2012). In-hospital mortality in derivation cohort was 7.73%, and 6.28% in validation cohort. Developed model has been designed with 4 independent echocardiographic predictors of in-hospital mortality: left ventricular ejection fraction (LVEF RR = 0.892; 95%CI = 0.854-0.932, P < 0.0005), aortic leaflet separation diameter (AOvs RR = 0.131; 95%CI = 0.027-0.627, P = 0.011), right ventricle diameter (RV RR = 2.675; 95%CI = 1.109-6.448, P = 0.028) and right ventricle systolic pressure (RVSP RR = 1.036; 95%CI = 1.000-1.074, P = 0.048). Model has good prognostic accuracy (AUROC = 0.84) and it retains good (AUROC = 0.78) when testing on the validation cohort. Risks for in-hospital mortality after PCI in ACS patients using echocardiographic measurements could be accurately predicted in contemporary practice. Incorporation of such developed model should facilitate research, clinical decisions, and optimizing treatment strategy in selected high risk ACS patients.

Isolated right ventricular dysfunction in patients with human immunodeficiency virus

BACKGROUND

HIV-infected individuals are at increased risk for pulmonary hypertension and cardiomyopathy, portending a poor prognosis. Right ventricular (RV) dysfunction is associated with worse outcomes in these conditions, yet its prevalence is poorly defined in HIV. We sought to determine the prevalence of RV dysfunction in an outpatient HIV cohort.

METHODS

Echocardiograms were evaluated from 104 HIV-infected adults. Measurements included estimated pulmonary arterial systolic pressure (PASP) and several measures of RV function, including tricuspid annular plane systolic excursion (TAPSE), RV longitudinal myocardial strain (RVLMS), RV fractional area change (RVFAC), and myocardial performance index (MPI).

RESULTS

Sixteen subjects (15%) had PASP >35 mm Hg, yet RV function did not differ significantly from those with normal estimated PASP. RV dysfunction defined by RVFAC <35% occurred in 11%. RVLMS had a median value of -27.3%, and individuals below the median had lower TAPSE but no differences in left ventricular ejection fraction (LVEF), PASP, or other measures. Dyspnea was associated with the lowest quintile of RVLMS (≥-21.05%). There were 6 subjects with LVEF <50%, and these individuals had lower TAPSE but no differences in PASP or other RV functional measures.

CONCLUSIONS

RV dysfunction was common as estimated PASP >35 mm Hg and LV dysfunction, but these findings did not cosegregate. RV dysfunction in HIV-infected individuals may be a separate entity from LV/global cardiomyopathy or pulmonary hypertension and deserves further study.

The Role of Right Ventricular Function in Mitral Valve Surgery

<p><b>Background:</b> An impaired right ventricular function is associated with a poor survival rate in patients with heart failure. Few investigations have analyzed the prognostic value of right ventricular function on the outcomes of mitral valve (MV) surgery. The objectives of this study were to define the effect of right ventricular function on postoperative outcomes after MV repair (MVP) or replacement (MVR).</p><p><b>Methods:</b> From September 2007 to February 2012, 335 consecutive patients underwent MVP or MVR at our institution. Preoperative transthoracic and transesophageal echocardiography (TEE) and postoperative TEE were used to define right ventricular function and MV performance. Preoperative right ventricular function was graded as normal to mild (grade 1-2) or as moderate to severe (grade 3-4). MV or tricuspid valve regurgitation was graded as non-trivial to mild (grade 0-2) or as moderate to severe (grade 3-4) preoperatively and postoperatively. Survival rate was evaluated at 1 year after surgery.</p><p><b>Results:</b> Of the 334 patients in the study, 280 patients showed a normal to a mildly impaired right ventricular function preoperatively (group 1). Fifty-four patients presented with moderate to severe right ventricular dysfunction (group 2). Patients with a compromised right ventricular function were more likely to undergo MVR (28.6% versus 53.7%, <i>P</i> <.001). The mean pulmonary artery pressure was 23.6 mm Hg in group 1 and 34 mm Hg in group 2 (<i>P</i> <.001). The left atrial diameter was 4.6 cm in group 1 and 5.3 cm in group 2 (<i>P</i> <.001). The 2 groups were not different with respect to operative mortality, but the patients in group 2 experienced more transfusion of blood products (588.4 mL versus 1180.6 mL, <i>P</i> <.001), longer intensive care unit stays (83.9 versus 149.6 hours, <i>P</i> <.001), and hospital stays (8.9 versus 12.8 days, <i>P</i> = .005). The rate of postoperative MV regurgitation was significantly higher in group 2 (1.8 versus 14.8%, <i>P</i> <.001). The overall 1-year survival rate was 92.5% in group 1 and 94.5% in group 2 (<i>P</i> = .59).</p><p><b>Conclusions:</b> This study has shown that a dysfunctional preoperative right ventricular function uses more resources and is associated with postoperative MV regurgitation, but it is not associated short- and mid-term mortality after MV surgery.</p>

Right ventricular ejection fraction measured by multigated planar equilibrium radionuclide ventriculography is an independent prognostic factor in patients with ischemic heart disease

BACKGROUND

The number of studies on the prognostic value of the right ventricular ejection fraction (RVEF) in patients with ischemic heart disease (IHD) is limited, whereas it is widely accepted that the left ventricular ejection fraction (LVEF) is a strong prognostic factor. We assessed whether RVEF measured by multigated planar equilibrium radionuclide ventriculography (RNV) is an independent prognostic factor in patients with IHD.

METHODS AND RESULTS

We retrospectively identified 347 consecutive patients with IHD (mean age 71 ± 11 years; 18% women) who underwent multigated planar equilibrium RNV between 2004 and 2008 to determine the LVEF, which also provided the RVEF (mean 44.7% ± 11.0%). We categorized patients according to RVEF in ≥40% (n = 240) and <40% (n = 107). Patients were followed for a median of 826 days (range 3-2,400) for the occurrence of events [all-cause mortality (n = 60), cardiac mortality (n = 33), and cardiac hospitalization (n = 78)]. Cox regression analysis with significant univariate predictors [coronary artery revascularization (P = .003), diuretics (P = .03), and statins (P < .001)] showed that an RVEF <40% was associated with a 2.90 (1.68-5.00)-fold higher risk of all-cause death. Accordingly, a decreased RVEF was associated with a 2.15 (1.34-3.43)-fold increase in the risk of cardiac hospitalization and a 5.11(2.32-11.23)-fold risk of cardiac death.

CONCLUSION

RVEF measured by multigated planar equilibrium RNV is an independent prognostic factor in patients with chronic IHD.

Evaluation of right and left ventricular function by quantitative blood-pool SPECT (QBS): Comparison with conventional methods and quantitative gated SPECT (QGS)

Though quantitative ECG-gated blood-pool SPECT (QBS) has become a popular tool in research settings, more verification is necessary for its utilization in clinical medicine. To evaluate the reliability of the measurements of left and right ventricular functions with QBS, we performed QBS, as well as first-pass pool (FPP) and ECG-gated blood-pool (GBP) studies on planar images in 41 patients and 8 healthy volunteers. Quantitative ECG-gated myocardial perfusion SPECT (QGS) was also performed in 30 of 49 subjects. First, we assessed the reproducibility of the measurements of left and right ventricular ejection fraction (LVEF, RVEF) and left and right ventricular end-diastolic volume (LVEDV, RVEDV) with QBS. Second, LVEF and RVEF obtained from QBS were compared with those from FPP and GBP, respectively. Third, LVEF and LVEDV obtained from QBS were compared with those from QGS, respectively. The intra- and inter-observer reproducibilities were excellent for LVEF, LVEDV, RVEF and RVEDV measured with QBS (r = 0.88 to 0.96, p < 0.01), while the biases in the measurements of RVEF and RVEDV were relatively large. LVEF obtained from QBS correlated significantly with those from FPP and GBP, while RVEF from QBS did not. LVEF and LVEDV obtained from QBS were significantly correlated with those from QGS, but the regression lines were not close to the lines of identity. In conclusion, the measurements of LVEF and LVEDV with QBS have good reproducibility and are useful clinically, while those of RVEF and RVEDV are less useful compared with LVEF and LVEDV. The algorithm of QBS for the measurements of RVEF and RVEDV remains to be improved.

Association Between A/C1166 Gene Polymorphism of the Angiotensin II Type 1 Receptor and Biventricular Functions in Patients With Acute Myocardial Infarction

BACKGROUND

Although there have been several association studies of angiotensin II type 1 receptor (AT1R, A/C1166) gene polymorphism in clinical endpoints such as myocardial infarction (MI), hypertension, aortic stiffness, and left ventricular mass, the relationship between AT1R polymorphism and biventricular function in acute anterior MI has not been studied before.

METHODS AND RESULTS

The study group comprised 132 consecutive patients who were admitted to the coronary care unit with their first acute anterior MI. Systolic and diastolic diameters, volumes, inflow properties, ejection fraction and myocardial performance index of both ventricles were measured. AT1R polymorphism was determined using polymerase chain reaction amplification. Based on A/C1166 polymorphism of AT1R, the patients were classified into 3 groups: group 1, A/A (n=91) genotype, group 2 A/C (n=28), and group 3 C/C (n=13) genotype. When the left ventricular and right ventricular echocardiographic functions were compared, all parameters of the 3 groups were found to be similar. No difference was detected in either the genotype distribution or allele frequencies between the patients and the controls for AT1R.

CONCLUSIONS

The results suggest that A/C1166 polymorphism of AT1R did not influence the risk of either acute MI or biventricular function after anterior MI.

Prognostic use of echocardiography 1 year after a myocardial infarction

BACKGROUND

Left ventricular (LV) and right ventricular (RV) function are known predictors of morbidity and mortality after an acute myocardial infarction (MI). However, the prognostic use of a late evaluation of cardiac function after an MI remains unclear.

METHODS

We analyzed echocardiograms obtained 1 year after MI in patients with LV dysfunction at baseline (ejection fraction [EF] < or = 40%) from 291 patients enrolled in the SAVE echocardiographic substudy who did not develop heart failure (HF) or a recurrent MI during this first year. Left ventricular EF and RV fractional area change were assessed.

RESULTS

After a median follow-up of 22 months after the 1-year echocardiogram, a low LVEF (< 30%) at 1 year was associated with an increased risk of death and/or HF (hazards ratio [HR] 2.7, 95% CI 1.3-5.3). Presence of RV dysfunction was also associated with an increased risk of death (HR 8.9, 95% CI 3.5-22.1), development of HF (HR 7.1, 95% CI 3.4-15.0), and the composite end point of death or HF (HR 7.6, 95% CI 4.1-14.2). In multivariate analyses, both low LVEF and RV dysfunction remained independently predictive of the composite end point of death or HF. Patients with biventricular dysfunction were at the greatest risk of death and/or HF (HR 19.4, 95% CI 8.2-46.0) in follow-up.

CONCLUSIONS

In a stable population of survivors of MI, impaired LV and RV function at 1 year after MI are independently and additively predictive of increased risk of HF or death.

Influence of Angiotensin-Converting Enzyme I/D Gene Polymorphism on the Right Ventricular Myocardial Performance Index in Patients With a First Acute Anterior Myocardial Infarction

BACKGROUND

The genetic influence on the myocardial performance index is uncertain, so the aim of the present study was to determine the effects of polymorphism of the angiotensin-converting enzyme (ACE) gene on the right ventricular myocardial performance index (RVMPI) after a first acute anterior myocardial infarction (MI).

METHODS AND RESULTS

The subjects were 116 patients with a first acute anterior MI. Based on the polymorphism of the ACE gene, they were classified into 3 groups: deletion/deletion (DD) genotype (group 1, n=45), insertion/deletion (ID) genotype (group 2, n=58), insertion/insertion (II) genotype (group 3, n=13). Echocardiograms were used to determine the RVMPI, left ventricular myocardial performance index (LVMPI), tricuspid E/A, tricuspid deceleration time and the left ventricular diameter diastolic and diameter systolic (LVDd and LVDs). RVMPI and LVMPI were significantly higher in the ACE DD group. Tricuspid E/A, DT, LVDd and LVDs showed no differences among the 3 groups.

CONCLUSION

The ID polymorphism of the ACE gene may affect RVMPI and LVMPI after a first acute anterior MI.

Percutaneous atrial septostomy for urgent palliative treatment of severe refractory cardiogenic shock due to right ventricular infarction

We report a novel palliative treatment to improve refractory cardiogenic shock due to right ventricular ischemia. We performed percutaneous atrial septostomy to create an atrial septal defect, which resulted in immediate right ventricular decompression and increased left ventricular filling associated with prompt and dramatic hemodynamic and clinical improvement.

Evaluation of left and right ventricular functional parameters with automatic edge detection program of ECG gated blood SPET

An analysis program for ECG gated, blood pool, single photon emission tomography (SPET GBP) is available. This program permits the automatic evaluation of left and right ventricular function, but its reliability has not been thoroughly assessed. The objective of this investigation was to examine the reliability of the parameters derived from SPET GBP. Fifty-three patients who had undergone both SPET GBP and planar, ECG gated, blood pool scintigraphy (planar GBP) were enrolled in the study. Planar GBP was performed with a single-headed gamma camera. From a left anterior oblique projection, data were acquired at 24 frames/cardiac cycle with ECG gating during the equilibrium state. SPET GBP was carried out utilizing a triple-headed gamma camera, with 60 projection views over 360 degrees, with 60 s per view, in 16 frames/cardiac cycle. Left ventricular ejection fraction (LVEF) and right ventricular ejection fraction (RVEF) were calculated by using the analysis program. The reproducibility of these values and the correlation between SPET and planar GBP were assessed. To evaluate the effect of cut-off frequencies of a Butterworth filter, six different cut-off frequencies (order=8, 0.3-1.0 Nyquist) were tested with data obtained from 12 patients. The reproducibility of LVEF by SPET GBP was satisfactory (intra-observer, r=0.95; inter-observer, r=0.96), whereas reproducibility of RVEF by SPET GBP was fair (intra-observer, r=0.83; inter-observer, r=0.83). LVEF with SPET GBP was well correlated (y=1.1x+6.62, r=0.85, P<0.01) with LVEF readings of planar GBP. However, LVEF with SPET GBP was overestimated (mean difference of 12) in comparison with that of planar GBP. The RVEF derived from SPET GBP showed poor correlation (y=0.52x+33, r=0.53, P<0.01) with planar GBP. No significant effect of cut-off frequencies of Butterworth filters was evident in the calculation of LVEF and RVEF (P=0.48 and 0.67) with SPET GBP. It is concluded that SPET GBP with QBS is useful for the evaluation of LVEF. However, measurement of the RVEF showed lower reproducibility compared with measurement of the LVEF.

Precardiopulmonary bypass right ventricular function is associated with poor outcome after coronary artery bypass grafting in patients with severe left ventricular systolic dysfunction

Patients with severe left ventricular systolic dysfunction (LVSD) undergoing coronary artery bypass grafting (CABG) have an increased risk for morbidity and mortality. The purpose of this study was to assess the association of pre-CABG right ventricular (RV) function with outcome for patients with severe LVSD. We performed a retrospective evaluation of 41 patients with severe LVSD (left ventricular ejection fraction [LVEF] < or =25%) scheduled for nonemergent CABG. Data were obtained from review of medical records, transesophageal echocardiography tapes, and phone interview. The pre- and post-cardiopulmonary bypass (CPB) LVEF and the RV fractional area of contraction (RVFAC) were calculated by using intraoperative transesophageal echocardiography. Group 1 patients had an RVFAC < or =35% (n = 7), whereas Group 2 patients had RVFAC >35% (n = 34). The durations of mechanical ventilation and of intensive care unit and hospital stays are presented as the median. Pre-CABG LVEF was similar between Groups 1 and 2 (15.8% +/- 3.3% versus 17.8% +/- 3.9%). Compared with Group 2, Group 1 patients required greater duration of mechanical ventilation (12 days versus 1 day; P < 0.01), longer intensive care unit (14 versus 2 days; P < 0.01) and hospital (14 versus 7 days; P = 0.02) stays, had a more frequent incidence and severity of LV diastolic dysfunction, and had a smaller change in LVEF immediately after CPB (4.1% +/- 8.3% versus 12.5% +/- 9.2%; P = 0.03). All Group 1 patients died of cardiac causes within 2 yr of surgery; five died during the same hospital admission. Three Group 2 patients died: one of colon cancer at 18 mo after CABG and two of cardiac causes 24 and 48 mo after surgery. A fourth patient was awaiting cardiac transplantation 4 yr after surgery. The remaining Group 2 patients were New York Heart Association Classification I or II. For patients with severe LVSD undergoing CABG, pre-CPB RV dysfunction was associated with poor outcome. Patients with RVFAC >35% had a relatively uneventful perioperative course and good long-term survival, whereas patients with RVFAC < or =35% had a poor early and late outcome. Assessment of RV function is useful to further assess the risk of CABG.

IMPLICATIONS

Right ventricular function before cardiopulmonary bypass is associated with poor outcome after coronary artery surgery in patients with poor left ventricular function.

Right ventricular dysfunction and risk of heart failure and mortality after myocardial infarction

OBJECTIVES

The aim of this study was to determine the prognostic value of right ventricular (RV) function in patients after a myocardial infarction (MI).

BACKGROUND

Right ventricular function has been shown to predict exercise capacity, autonomic imbalance and survival in patients with advanced heart failure (HF).

METHODS

Two-dimensional echocardiograms were obtained in 416 patients with left ventricular (LV) dysfunction (ejection fraction [LVEF] < or = 40%) from the Survival And Ventricular Enlargement (SAVE) echocardiographic substudy (mean 11.1 +/- 3.2 days post infarction). Right ventricular function from the apical four-chamber view, assessed as the percent change in the cavity area from end diastole to end systole (fractional area change [FAC]), was related to clinical outcome.

RESULTS

Right ventricular function correlated only weakly with the LVEF (r = 0.12, p = 0.013). On univariate analyses, the RV FAC was a predictor of mortality, cardiovascular mortality and HF (p < 0.0001 for all) but not recurrent MI. After adjusting for age, gender, diabetes mellitus, hypertension, previous MI, LVEF, infarct size, cigarette smoking and treatment assignment, RV function remained an independent predictor of total mortality, cardiovascular mortality and HF. Each 5% decrease in the RV FAC was associated with a 16% increased odds of cardiovascular mortality (95% confidence interval 4.3% to 29.2%; p = 0.006).

CONCLUSIONS

Right ventricular function is an independent predictor of death and the development of HF in patients with LV dysfunction after MI.

Serial Doppler echocardiographic assessment of left and right ventricular performance after a first myocardial infarction

We sought to investigate the relation between left ventricular (LV) and right ventricular (RV) function assessed with the Doppler-derived myocardial performance index (MPI), to assess serial changes, and to investigate the prognostic value of biventricular assessment of cardiac function after a first myocardial infarction (MI). To do so, serial Doppler echocardiography was performed in 77 consecutive patients with a first MI. Right ventricular MPI correlated significantly with LV MPI (r = 0.51, P <.0001). In patients with echocardiographic signs of RV MI, the RV MPI was significantly higher (0.59 +/- 0.18 versus 0.44 +/- 0.19, P =.001), whereas no difference in LV MPI was seen (0.55 +/- 0.19 versus 0.56 +/- 0.13, P = not significant). Right ventricular MPI showed a rapid normalization during follow-up, whereas LV MPI did not decrease. During follow-up, 23 patients died of cardiac causes or were readmitted because of worsening heart failure. Multivariate Cox analysis indicated LV MPI (relative risk 4.9 [95% CI 1.8-13.5], P =.002) and RV MPI (relative risk 3.8 [1.3-17.0], P =.01) to be predictors of cardiac events. Thus the RV MPI is frequently abnormal after a first MI but normalizes rapidly on follow-up, and biventricular assessment of cardiac function may improve the prognostic accuracy compared with LV assessment alone.