Right Ventricular Infarction Research Articles

Right Ventricular Function Suffers From Reperfusion Delay: Tissue Doppler Study

In this study, impact of reperfusion delay on adverse cardiac events and right ventricular (RV) function in patients with acute right ventricular myocardial infarction (RVMI) was assessed. In 70 patients with RVMI, RV function was assessed by M-mode tricuspid annular plane systolic excursion (TAPSE) and by pulsed wave tissue Doppler echocardiography (TDE). Right ventricular early (E'(T)) and late diastolic (A'(T)), peak systolic tricuspid annular velocity, (S'(T)) and right ventricular myocardial performance index (RVMPI) were measured. Patients were divided into 2 groups according to the time between the onset of symptoms and percutaneous transluminal coronary angioplasty (PTCA)-group 1 (n = 25), < or =3 hours and group 2 (n = 45), > 3 hours. During 30-day follow-up, we assessed adverse cardiac events like the following: death, cardiogenic shock, need for intra-aortic counterpulsation, temporary transvenous pacing support (PCM), presence of ventricular septal defect (VSD), cardiac tamponade, or free wall rupture. Group 1 had significantly higher values of E'(T), S'(T), and TAPSE than group 2. RVMPI was significantly elevated in group 2. A total of 13 (18.2%) patients had a cardiac event, 5 patients (7.1%) died. We observed an increase of cardiac events in patients with reperfusion delayed more than 3 hours (P = .056). TAPSE-derived and TDE-derived right ventricular systolic and early diastolic velocities were less affected in patients with shorter time from pain onset to opening of the occluded right coronary artery (RCA). Presented initial data show that the tissue Doppler technique may be useful for identification of patients with RV infarction with higher rate of adverse cardiac events including death.

Tricuspid Annular Velocity Assessed by Doppler Tissue Imaging as a Marker of Right Ventricular Involvement in the Acute and Late Phase after a First ST Elevation Myocardial Infarction

Right ventricular (RV) involvement in patients with ST elevation myocardial infarction (STEMI) is a clinically important problem. The aim of this study was to evaluate the use of tricuspid annular velocity assessed by Doppler tissue imaging (DTI) as a marker of RV involvement in patients with a first STEMI. Seventy-one patients with a first STEMI were examined by echocardiography before discharge and after 6 months. The patients were compared to 31 healthy subjects (HS). The diagnosis of RV infarction was based on the presence of >or= 1 mm ST elevation in the right precordial ECG lead V4R. Tricuspid annular systolic and diastolic velocities using pulsed-wave DTI were recorded at the RV free wall. At day 1, tricuspid annular velocities were significantly reduced in patients with, compared to those without, ST elevation in V4R (11.1 vs. 13.7 cm/sec, 9.4 vs. 13.1 cm/sec and 14.1 vs. 15.9 cm/sec for systolic, early, and late diastolic velocities, respectively; P < 0.01). With a cutoff value for a tricuspid annular systolic velocity of 13 cm/sec, sensitivity and specificity for identifying patients with ST elevation in V4R were 89% and 71%, respectively. After 6 months, both tricuspid annular systolic and diastolic velocities in patients with RV infarction had increased significantly, but only tricuspid annular systolic velocity was still reduced compared to HS (12.3 vs. 14.7 cm/sec; P < 0.01). Tricuspid annular velocities assessed by DTI may be used as a marker of RV involvement in the acute and the late phase after a first STEMI.

Right Ventricular Infarction and Tissue Doppler Imaging - Insights From Acute Inferior Myocardial Infarction After Primary Coronary Intervention -

Tissue Doppler imaging (TDI) data for acute inferior myocardial infarction (MI) patients who have received primary percutaneous coronary intervention (PCI) are sparse. One hundred and sixty-five patients received primary PCI for acute inferior MI were enrolled. Right ventricular infarction (RVI) was defined as a culprit lesion proximal to the right ventricular branch of right coronary artery (RCA). Echocardiograms and TDI were obtained within 6 h after primary PCI. The prevalence of multi-vessel disease in the RCA-P culprit group (50%) was higher than that in other groups (39% of RCA-D culprit, 43% of left circumflex artery (LCX) culprit). The myocardial performance index (MPI) of the lateral tricuspid annulus provides discriminatory power for identifying RVI, whereas systolic velocity (Sm) of the lateral tricuspid annulus does not. Lateral mitral annular MPI divided by the lateral tricuspid annular MPI is a reliable index for identifying a culprit lesion (>1.06 predicts culprit over LCX; <0.96 predicts culprit over RCA-P and RVI). Kaplan-Meier survival curves revealed that late cardiovascular events were more likely in RVI patients. However, multivariate Cox proportional hazards analysis revealed that the most important factor in hard events and all cardiovascular events was multivessel disease. TDI is useful for identifying RVI and culprit lesions in inferior MI patients received primary PCI. RVI itself isn't associated with 1-year hard events and all cardiovascular events.

Malignant Ventricular Arrhythmias in Patients With Acute Right Ventricular Infarction Undergoing Mechanical Reperfusion

Patients with acute right ventricular (RV) infarctions are prone to ventricular arrhythmias, but little is known regarding the temporal patterns of these arrhythmias, their impact on outcomes, or their relation to the severity of RV impairment. The aim of this study was to examine the impact of malignant ventricular arrhythmias (MVAs) complicating acute RV infarction. A further aim was to determine whether the degree of RV impairment was a predisposing factor to MVAs. The charts of 48 patients with acute RV infarctions were reviewed for documented MVAs. Temporal presentation, relating to reperfusion, and in-hospital outcomes were tabulated. Echocardiograms were reviewed to quantify RV impairment. MVAs occurred in 38% of patients, with multiple episodes (electrical storm) in 8.3%. MVAs developed before reperfusion (72% of patients), abruptly with reperfusion (11%), or after reperfusion (22%). Patients with MVAs had larger infarcts (peak creatine phosphokinase 3,027 vs 1,848 U/L, p = 0.03) and trended toward worse RV function (fractional shortening 27% vs 34%, p = 0.08). In-hospital mortality (patients with MVAs 17% vs 6.7%, p = 0.35), intensive care days (patients with MVAs 7.1 +/- 10 vs 3.9 +/- 2.5, p = 0.39), and hospital days (patients with MVAs 10.3 +/- 10 vs 8.0 +/- 5.1, p = 0.57) were similar between groups. Patients with electrical storm had longer intensive care stays (18.0 +/- 18.5 vs 4.0 +/- 2.5 days, p = 0.02) and hospital stays (20.5 +/- 17 vs 7.9 +/- 5.0 days, p = 0.05). In conclusion, MVAs are common in acute RV infarctions. They frequently occur before reperfusion and are associated with larger infarcts. With reperfusion, MVAs had little impact on intensive care and hospital stays or in-hospital mortality, except in patients with electrical storm.

Cellular cardiac regenerative therapy in which patients?

Cell-based myocardial regenerative therapy is undergoing experimental and clinical trials in order to limit the consequences of decreased contractile function and compliance of damaged ventricles owing to ischemic and nonischemic myocardial diseases. A variety of myogenic and angiogenic cell types have been proposed, such as skeletal myoblasts, mononuclear and mesenchymal bone marrow cells, circulating blood-derived progenitors, adipose-derived stromal cells, induced pluripotent stem cells, umbilical cord cells, endometrial mesenchymal stem cells, adult testis pluripotent stem cells and embryonic cells. Current indications for stem cell therapy concern patients who have had a left- or right-ventricular infarction or idiopathic dilated cardiomyopathies. Other indications and potential applications include patients with diabetic cardiomyopathy, Chagas heart disease (American trypanosomiasis), ischemic mitral regurgitation, left ventricular noncompacted myocardium and pediatric cardiomyopathy. Suitable sources of cells for cardiac implant will depend on the types of diseases to be treated. For acute myocardial infarction, a cell that reduces myocardial necrosis and augments vascular blood flow will be desirable. For heart failure, cells that replace or promote myogenesis, reverse apoptopic mechanisms and reactivate dormant cell processes will be useful. It is important to note that stem cells are not an alternative to heart transplantation; selected patients should be in an early stage of heart failure as the goal of this regenerative approach is to avoid or delay organ transplantation. Since the cell niche provides crucial support needed for stem cell maintenance, the most interesting and realistic perspectives include the association of intramyocardial cell transplantation with tissue-engineered scaffolds and multisite cardiac pacing in order to transform a passive regenerative approach into a ‘dynamic cellular support’, a promising method for the creation of ‘bioartificial myocardium’.

Anti‐ischemic effects of inotropic agents in experimental right ventricular infarction

Right ventricular (RV) function is an important determinant of survival after myocardial infarction. The efficacy of reperfusion therapy might be increased by the cardioprotective action of inotropic agents, which are used for symptomatic therapy in situations with compromised hemodynamics. Therefore, we used a porcine model of RV ischemia and reperfusion (IR) injury to study the influence of milrinone, levosimendan and dobutamine on the extent and degree of myocardial injury. IR injury was induced by temporary ligation of the distal right coronary artery for 90 min, followed by 120 min of reperfusion. Treatment was initiated 30 min after coronary artery occlusion. A bolus of milrinone (n=12; 50 microg/kg) and levosimendan (n=10; 24 microg/kg) was applied in different groups, followed by continuous infusion of the drugs at 0.5 and 0.2 microg/kg/min, respectively. The effects on myocardial injury and inflammation were compared with a control (n=12) and a dobutamine group (n=10), where treatment was started with an infusion of 5 microg/kg/min. Milrinone and levosimendan reduced the resulting infarct size with respect to the area at risk (41.7+/-10.2%, 45.7+/-8.1%) when compared with the control group (58.3+/-6.1%). In contrast, dobutamine had no effect (55.8+/-7.7%). All drugs reduced the number of neutrophils infiltrating into the different myocardial regions and the circulating levels of interleukin-6. Increased levels of tumor necrosis factor alpha during reperfusion were only abated by milrinone and levosimendan. Cardioprotective properties of milrinone and levosimendan were demonstrated for the first time in a clinically relevant model of RV infarction.

Right Ventricular Edema Complicating Acute Inferior Myocardial Infarction as Demonstrated by T 2 -Weighted Cardiovascular Magnetic Resonance

Right ventricular (RV) involvement after acute myocardial infarction (MI) carries an adverse prognosis, but in the majority of patients RV function recovers fully over time.1 It is believed that the lower oxygen requirement of the RV and higher collateral flow make the RV more resistant to ischemia. In the absence of infarction, myocardial ischemia leads to intracellular and subsequently extracellular edema, which may contribute to reversible RV dysfunction after acute MI. Cardiovascular magnetic resonance (CMR) is the optimal tool to image the RV because it is not constrained by imaging windows or insufficient spatial resolution. CMR can assess RV function, volume, and infarction.2,3 Furthermore, tissue edema can be depicted in vivo using T …

Extracorporeal Life Support: A Simple and Effective Weapon for Postcardiotomy Right Ventricular Failure

Postcardiotomy right ventricular (RV) failure develops during the perioperative period following pulmonary hypertensive crisis or acute myocardial infarction. This study reports our institutional experience in treating these patients with extracorporeal life support (ECLS). Between June 2002 and July 2005, 46 adults were treated with ECLS for postcardiotomy shock. Acute RV failure was the cause of support in 14 (30%). Patient mean age was 55.7 +/- 15.4 years. Cardiac pathologies were valvular (n = 7), coronary (n = 1), combined coronary and valvular disease (n = 2), complex congenital heart (n = 2), aortic aneurysm (n = 1), and cardiomyopathy post heart transplant (n = 1). The triggers of RV failure were pulmonary hypertension (n = 6), RV infarction (n = 4), and not defined (n = 4). Patients were supported on ECLS for a mean duration of 71 +/- 52 h (range, 10-183 h). Major complications included acute renal failure requiring hemodialysis (n = 4), reexploration for bleeding (n = 2), and acute subdural hematoma (n = 1). Nine (64%) patients were successfully weaned from ECLS, and seven (50%) survived to discharge. Preexisting pulmonary hypertension had a favorable tendency for weaning, and acute renal failure requiring hemodialysis correlated with in-hospital mortality. ECLS is beneficial for treating postcardiotomy RV failure when conventional therapy is exhausted. As it can be deployed rapidly and does not require resternotomy for weaning, ECLS could be regarded as the first choice of mechanical support for postcardiotomy RV failure.

High degree Atrioventricular block in patients with acute inferior Myocardial Infarction with and without Right Ventricular involvement.

To determine the influence of time on development of high degree Atrioventricular (AV) block in patients with inferior Myocardial Infarction (MI), its association with Right Ventricular (RV) infarction and its ultimate morbidity and mortality. A descriptive study. The Emergency Department (ED) and the units of adult cardiology at National Institute of Cardiovascular Diseases (NICVD), Karachi, from October 2006 to March 2007. Patients presented at ED with typical chest pain and subsequently diagnosed by standardized diagnostic criteria as having inferior MI were recruited prospectively. Patients were first analyzed on the basis of absence (Group A) or presence (Group B) of high degree AV block regardless of RV infarction. Then after patients were divided into two groups, those without RV infarction (Group I) and with RV infarction (Group II). Each group was further sub-divided as Ia, IIa and Ib, IIb depending on absence or presence of high degree AV block respectively. Each group was analyzed for comparisons with different variables for prediction of influence of time, proportion of RV infarction, association of AV block with RV infarction, complication profile and inmortality. Of the 220 patients with inferior MI, 52 (23.6%) had high degree AV block and 83 (37.7%) had RV infarction. They were older in age (p< 0.003). Patients who took more time to seek medical treatment from onset of symptoms were more prone to develop AV block (p<0.001). Among patients with block, 73% received thrombolytic therapy (p<0.009) and temporary pacemaker (TPM) was implanted in 75% (p<0.0001). Mortality was significantly high in those patients (p<0.0001). In group II, 61.4% presented with sinus rhythm (p<0.001). TPM was implanted to 31.3% (p<0.0001). In the 4 days of hospital course, 8.4% of patients with RV infarction developed AV block (p<0.005), whereas 10.8% of patients without RV infarction experienced post MI angina (p<0.031). Mortality was found significantly high when block was associated with RV infarction (p<0.007). No significant difference was found in response to atropine, volume replacement or streptokinase administration and reverting of block to sinus rhythm. Patients with inferior MI who took more time to seek medical treatment were found to be more prone to develop high degree AV block. RV infarction was found in about 38% of patients defined a high risk subgroup. High degree AV block significantly influenced the outcome when associated with RV infarction, leading to high mortality.

P-204 Value of Higher ST Elevation in Lead 3 than in Lead 2 for Predicting in-Hospital Outcome among Patients with Acute RV Infarction

P-204 Value of Higher ST Elevation in Lead 3 than in Lead 2 for Predicting in-Hospital Outcome among Patients with Acute RV Infarction

THE USEFULNESS OF B-TYPE NATRIURETIC PEPTIDE IN THE EARLY DIAGNOSIS OF RIGHT VENTRICULAR INFARCTION

PURPOSE: 19–51% of inferior acute myocardial infarction(AMI) patients combine with right ventricular infarction(RVI). RVI is associated with a highly increased in-hospital mortality. Therefore, early diagnosis of RVI in inferior acute myocardial infarction is very important. This study was planned to investigate the usefulness of B-type natriuretic peptide(BNP) in the early diagnosis of RVI.

Establishment of a porcine right ventricular infarction model for cardioprotective actions of xenon and isoflurane

Right ventricular (RV) function is an important determinant of post-operative outcome. Consequences of RV infarction might be limited by pre-conditioning with volatile anesthetic drugs. Therefore, we used a porcine model of RV ischemia and reperfusion (IR) injury to study the influence of isoflurane and xenon on the extent and degree of myocardial injury. IR injury was induced by a 90-min ligation of the distal right coronary artery and 120-min reperfusion in thiopental anesthetized pigs. A control group (n=12) was compared with two groups, which received either 0.55 minimum alveolar concentration (MAC) isoflurane (n=10) or xenon (n=12) starting 60 min before ischemia. Myocardial injury was described by three criteria: the infarct size related to area at risk (IS/AAR), the infiltration of neutrophils as determined by myeloperoxidase (MPO) activity, and the plasma levels of tumor necrosis factor alpha (TNFalpha), interleukin 6 (IL-6), myoglobin and troponin-T (TnT). IS/AAR was reduced from 58.3+/-6.2% in the control group to 41.8+/-7.8% after isoflurane and 42.7+/-8.5% after xenon pre-treatment, which equals an absolute reduction of 16.5% [95% confidence interval (CI): 10.9-22.1] and 15.5% (95% CI: 10.1-20.9). The maximum increase of TnT could be observed within the xenon group. Both treatment groups were characterized by lower MPO activity, in the infarct and periinfarct region and lower plasma concentrations of TNFalpha and IL-6. It could be demonstrated for the first time in a model of RV infarction that the continuous application of isoflurane or xenon before, during and after ischemia reduced the extent (size) and severity (inflammation) of myocardial injury.

Right ventricular stunning in inferior myocardial infarction

Aim To assess right ventricular (RV) function in patients with inferior myocardial infarction (IMI) and to observe changes following thrombolysis. Background RV dysfunction occurs in 30% of patients with IMI. The extent of such involvement and its potential, recovery has not been determined. Methods We studied 30 patients with acute IMI (age 56 ± 12 years), on admission, day 7 and day 30 post thrombolysis. No patient had clinical signs of RV failure. RV segmental function was assessed from free wall long axis and global function from filling and ejection velocities. Values were compared with 15 age-matched controls. Results On admission, RV long axis amplitude, systolic and diastolic velocities were depressed (2.09 ± 0.39 vs 2.6 ± 0.3 cm, 8.18 ± 1.8 vs 10.0 ± 2.0 cm/s and 6.9 ± 2.7 vs 10.0 ± 2.5 cm/s, p < 0.01 for all) and global function impaired; reduced Z ratio (0.85 ± 0.07 vs 0.9 ± 0.04, p < 0.01), raised Tei index (0.49 ± 0.26 vs 0.3 ± 0.1, p < 0.001) and prolonged t-IVT (8.16 ± 3.9 vs 4.8 ± 2 s/m, p < 0.01) compared to controls. After thrombolysis, RV long axis amplitude (2.28 ± 0.3 cm, p < 0.05), systolic velocity (10.0 ± 2.7 cm/s, p < 0.01), early diastolic velocity (8.3 ± 2.16, p < 0.05), Z ratio (0.9 ± 0.05, p < 0.01), Tei index (0.34 ± 0.17, p < 0.01) and t-IVT (6.2 ± 2.7 s/m, p < 0.05) all normalised at day 30. Only 4 (13%) patients remained with RV long axis amplitude and one with t-IVT and Tei index values outside the normal 95% CI at day 30. RV inflow diameter and tricuspid regurgitation did not change. Conclusion In IMI, RV segmental and global functions are acutely impaired, and recover in 87% of patients following thrombolysis. In the absence of clear evidence for RV infarction the disturbances in the remaining 13% may represent stunned myocardium that may demonstrate delayed recovery.

Silent inferior myocardial infarction with extensive right ventricular scarring

Right ventricular infarction (RVI) occurs in approximately 50% of patients with inferior myocardial infarction (MI). The assessment of RVI is important for identifying patients being at increased risk of in hospital mortality and poorer prognosis if impaired right ventricular (RV) systolic function is present. We report the case of an asymptomatic 38-year-old male who sustained a silent inferior myocardial infarction with extensive RV involvement. There was no history of myocardial ischemia and cardiovascular risk factors. Therefore, first cardiac magnetic resonance (CMR) imaging using delayed enhancement (DE) was performed and revealed a transmural inferior wall myocardial infarction of LV with extensive involvement of RV. This case illustrates the difficulties of conventional imaging modalities and invasive coronary angiography to depict an inferior myocardial infarction with RV involvement.

Right Ventricular Strain and Strain Rate Properties in Patients with Right Ventricular Myocardial Infarction

This study was planned to assess strain and strain rate properties of right ventricle in patients with RV myocardial infarction. Thirty patients with acute inferior myocardial infarction were included in this study. The presence of right ventricular infarction in association with an inferior myocardial infarction was defined by an ST-segment elevation 0.1 mV in lead V4 R. According to this definition, 15 patients had electrocardiographic signs of inferior myocardial infarction without right ventricular infarction (group I), and 15 patients had electrocardiographic signs of inferior myocardial infarction with right ventricular infarction (group II). Echocardiography was performed using a Vivid 5 System (GE Ultrasound; Horten, Norway) and a 2.5-MHz transducer. 2-dimensional color doppler myocardial imaging (CDMI) data for longitudinal function were recorded from the RV free wall using standard apical view. Offline analysis of the myocardial color Doppler data for regional velocity (V), strain rate (Sr), and strain (S) curves was performed using a special software program (EchoPac 6.4 Vingmed, Horten, Norway). They were assessed in basal, middle and apical segments of the RV. The differences between different groups were assessed with the Mann-Whitney U-test. A value of P < 0.05 was considered statistically significant. Systolic tissue velocity, strain, strain rate of basal (4.8 +/- 0.8 cm/s vs 6.5 +/- 1.2 cm/s, -12 +/- 3% vs -24 +/- 5%, 1.28 +/- 0.3/s vs -1.9 +/- 0.4/s; P < 0.001, <0.001, <0.001, respectively) and mid (4.2 +/- 0.5 cm/s vs 5.4 +/- 0.5 cm/s, -16 +/-3% vs -26 +/- 4%, -1.2 +/- 0.3/s vs -2.1 +/- 0.3/s; P < 0.001, <0.001, <0.001, respectively) segments of right ventricle were significantly lower in patients with RV infarction than in patients without RV infarction. There were no differences between groups for apical strain, strain rate, and systolic tissue velocity. This study demonstrates that right ventricular strain and strain rate were lower in patients with left ventricular inferior wall myocardial infarction with, compared to without, right ventricular infarction.

Myocardial infarction: contemporary management strategies

Myocardial infarction (MI) is a common clinical diagnosis, associated with significant morbidity and mortality, not only in the short term, but also years following the index event. A more complete understanding of the pathophysiology of MI has ushered the era of multipronged treatment approach, with a combination of goal-directed revascularization, a broad adjunctive pharmacological therapy and aggressive secondary prevention measures. The goals of this article are to review the basic pathophysiological processes, which lead up to a clinical diagnosis of MI, to highlight the essential elements of clinical presentation and to summarize the evidence for comprehensive therapy. Emphasis has been placed on the choice of primary reperfusion therapy for ST-elevation MI, on risk-stratification of patients with non-ST elevation MI, and on rationale behind the selection of anti-ischaemic and antithrombotic therapy. Finally, evidence-based approach to secondary prevention is outlined.

The ECG Pattern of Isolated Right Ventricular Infarction during Percutaneous Coronary Intervention

Isolated right ventricular infarction (RVI) is a rare event. The electrocardiographic (ECG) pattern of RVI, ST-elevation in lead V4R and in anterior chest leads V1-3 is similar to that of a proximal occlusion of a small, nondominant right coronary artery (RCA). The ECG changes may be misinterpreted as signs of infarction of the anterior wall. This paper describes a case of isolated temporary occlusion of the major side branches of the RCA during percutaneous coronary intervention, recognized by angiography findings and typical ECG changes. This case demonstrates how one might avoid wrong decisions even in the catheterization laboratory by putting attention to the anatomical interpretation of the ECG.

Comparison of Late Survival in Patients With Cardiogenic Shock Due to Right Ventricular Infarction Versus Left Ventricular Pump Failure Following Primary Percutaneous Coronary Intervention for ST-Elevation Acute Myocardial Infarction

This study compared late survival after primary percutaneous coronary intervention (PCI) in patients with cardiogenic shock due to right ventricular (RV) infarction versus left ventricular (LV) pump failure. Consecutive patients with ST-elevation myocardial infarction treated with primary PCI (n = 2,496) were prospectively enrolled in a registry from 1984 to 2004. Cardiogenic shock occurred before PCI in 189 patients (7.6%). Shock was attributed to predominant RV infarction when there was right coronary artery occlusion with preserved LV function and increased right atrial pressure. Patients with shock due to RV infarction (n = 30) versus LV pump failure (n = 136) had fewer previous infarctions (10% vs 29%, p = 0.03), less multivessel disease (20% vs 47%, p = 0.007), higher right atrial pressure (21 vs 16 mm, p = 0.003), and better LV ejection fraction (57% vs 32%, p <0.001). In-hospital mortality was lower with shock due to RV infarction (23% vs 50%, p = 0.01), and shock due to RV infarction was a significant independent predictor of late cardiac survival (hazard ratio 0.28, 95% confidence interval 0.13 to 0.62, p = 0.002). In conclusion, survival after primary PCI in patients with shock due to RV infarction is better than that in patients with shock due to LV pump failure. This is in contrast to most previous reports. Improved survival is likely related to lower risk profile and previously documented substantial recovery of RV function after primary PCI.

Contrast-Enhanced Cardiovascular Magnetic Resonance Imaging of Right Ventricular Infarction

We assessed the role of late enhancement cardiovascular magnetic resonance imaging (LE-CMR) for the diagnosis of right ventricular infarction (RVI). Right ventricular infarction occurs in about one-half of patients with inferior myocardial infarction (MI). It is associated with an unfavorable prognosis, but established methods often lack the diagnostic accuracy to detect it. Late enhancement cardiovascular magnetic resonance imaging accurately detects left ventricular MI. Thirty-seven patients with acute inferior MI were included. To test for RVI, they prospectively underwent a physical examination, an electrocardiogram (ECG) for ST-segment elevation in the V4r right precordial lead, and an echocardiogram. After coronary reperfusion, LE-CMR was performed for assessing presence and extent of late enhancement in the right ventricular (RV) wall. The LE-CMR data were compared with the other results; interobserver variability was assessed. The LE-CMR was repeated after 13 months. Late enhancement cardiovascular magnetic resonance imaging detected RVI in 21 of 37 (57%) patients with acute inferior MI. Interobserver variability was very good (kappa 0.83); physical exam was positive for RVI in 7 of 37 (19%) patients, V4r ECG in 13 of 37 (35%) patients, and echocardiogram in 6 of 37 (16%) patients. The LE-CMR findings for RVI showed only mild agreement with findings for RVI on physical exam (kappa 0.30), V(4)r ECG (kappa 0.38), and echocardiography (kappa 0.32). Irreversible injury of the RV persisted at 13 months (kappa 0.85). In patients with acute inferior MI, RVI is more frequently detected by LE-CMR than by current standard diagnostic techniques. Further CMR studies might allow for analyzing its clinical and prognostic relevance.

Initial report of percutaneous right ventricular assist for right ventricular shock secondary to right ventricular infarction

A 57-year-old female suffered an acute inferior ST segment elevation myocardial infarction. The patient failed thrombolysis and was urgently transferred for rescue percutaneous coronary intervention of the right coronary artery. She decompensated after reperfusion of the occluded RCA and developed cardiogenic shock from severe right heart failure refractory to IABP support and maximal pressors. A percutaneous right ventricular assist device was successfully implanted, which improved mean arterial pressure to a viable range and allowed withdrawal of inotropic medications. Right ventricular failure after infarction remains difficult to manage and has a high mortality. Intraaortic balloon pump and LVAD support have not proven beneficial in cardiogenic shock secondary to RV infarction. This is a report of the first insertion of a percutaneous right ventricular assist device for right ventricular support in a human. Further evaluation is warranted to evaluate the potential benefits of such a device as well as optimal timing of initiation of RV support.