Primary angioplasty for isolated right ventricular infarction.

We describe a case of isolated right ventricular infarction that has rarely been diagnosed antemortem. Electrocardiogram showed ST segment elevation in left precordial chest, right precordial chest, and inferior leads, which mimicked those of anterior and inferior left ventricular infarction. Coronary angiography revealed that culprit lesion was totally occluded right coronary artery. Infarcted artery was nondominant right coronary artery with branches supplying only right ventricular wall. Restoration of coronary blood flow was obtained by primary stenting and resulted in prompt ST segment normalization in all leads. Despite extensive right ventricular wall motion abnormality, subsequent right ventricular dysfunction was not observed.     

A rare case of isolated right ventricular infarction

We present a case of right ventricular infarct mimicking, on the electrocardiogram, an anterior myocardial infarction. The Grant method of vector electrocardiography is a seldom used tool but is a very accurate way of evaluating electrocardiograms and is as useful adjunct to pattern recognition.     

Isolated right ventricular infarction presenting as anterior wall myocardial infarction on electrocardiography

Isolated right ventricle infarction is extremely rare, and its electrocardiographic (ECG) signs may be misinterpreted or even missed, especially when a typical clinical picture is lacking. This paper describes a case of isolated right ventricle infarction, recognized only by echocardiography. The patient presented with ST-segment elevation in left precordial leads together with minimal ST-segment elevation in inferior leads on a 12-lead ECG. Angiography revealed the culprit right coronary artery, which was small and non-dominant. No significant obstructions were found in the left anterior descending artery. This case demonstrates that the ECG appearance of isolated right ventricle infarction may mimic anterior wall infarction and can be easily missed if not suspected.     

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 V_1‐3 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.     

Right ventricular infarction mimicking extensive anterior infarction

Two patients with inferior infarction complicated by right ventricular infarction are presented. Both manifested electrocardiographic changes involving the anterior chest leads with initial S-T segment elevation followed by loss of R waves and the development of QS complexes mimicking anterior infarction. Cardiac catheterization showed right coronary artery occlusion with normal left coronary system and anterior wall motion in each case. Radionuclide angiocardiography showed dilated poorly contracting right ventricles. The ECG changes of "anterior infarction" in these patients were therefore due solely to right ventricular injury.     

Isolated acute occlusion of a large right ventricular branch of the right coronary artery following coronary balloon angioplasty: The only true 'model' to study ECG changes in acute, isolated right ventricular infarction

An isolated right ventricular infarction occurs rarely and dataon its electrocardiographic appearance and underlying angiographicallyproven cause are scarce. The electrocardiographic response ofacute right ventricular ischaemia is often obscured by the coexistingforces of the ischaemic mass of the inferior wall of the leftventricle when the right coronary artery itself becomes occluded.Percutaneous transluminal coronary angioplasty of the rightcoronary artery may cause an isolated occlusion of a right ventricularbranch. We encountered this phenomenon in nine patients. Inall, it led to acute isolated right ventricular ischaemia withST elevations in the right precordial leads (V₁–V₃, V₃Rand V₄R on the electrocardiogram. We conclude that the ECG pattern of pure right ventricular ischaemiacan be seen when an isolated occlusion of a large right ventricularbranch occurs, for example as a complication of percutaneoustranslummal coronary angioplasty.     

Right ventricular infarction

Right ventricular infarction commonly occurs in association with acute inferior left ventricular infarction, but is uncommon when infarction involves other areas of the left ventricle. Evidence of right ventricular infarction often can be detected by physical examination, electrocardiography, echocardiography, or radionuclide ventriculography. However, hemodynamically significant infarction (i.e., hypotension or shock) is much less frequent, occurring in approximately 10% of patients with other evidence of right ventricular infarction. Right ventricular infarction increases ventricular stiffness, thereby impeding diastolic filling. This results in hemodynamic changes similar to those found in constrictive pericarditis: elevated systemic venous pressure, a Y descent greater than the X descent, and an inspiratory increase in venous pressure. The increase in venous pressure generally equals or even exceeds left atrial pressure. When hypotension or shock occurs, expansion of vascular volume is generally employed as initial therapy. In nonresponders, dobutamine or similar inotropic agents may be helpful. The prognosis during the acute phases is guarded, but, in survivors, prognosis is favorable and generally related to the extent of left ventricular involvement.     

Right ventricular infarction following percutaneous coronary rotational atherectomy

We describe a case of right ventricular infarction complicating percutaneous coronary rotational atherectomy of sequential calcified right coronary artery lesions. Right ventricular infarction resulted from occlusion of two right ventricular marginal branches during successful atherectomy of the right coronary artery.     

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.     

Echocardiographic features of right ventricular infarction

In a series of 75 consecutive patients with transmural acute myocardial infarction (AMI) a right-to-left ventricular filling pressure ratio equal to or greater than 0.65 (RVFP/LVFP greater than or equal to 0.65) was assumed to be indicative of associated right ventricular infarction (RVI). Out of 45 patients with inferoposterior myocardial infarction, 11 (24%) had such hemodynamic evidence of right ventricular infarction (group A). The remaining 34 patients with inferoposterior myocardial infarction (group B) and the 30 patients with anterior myocardial infarction did not. Time-motion and two-dimensional echocardiographic examinations were performed 7-10 days after admission in the 62 patients who survived. Right ventricular wall asynergy was found in six of eight group A patients. In three of these, right ventricular dilatation was also present. No patient in group B with inferior infarction or with anterior infarction showed abnormal right ventricular wall motion. While hemodynamic monitoring seems presently the most specific diagnostic method and it is of invaluable help in the choice of the best pharmacological therapy of right ventricular failure due to RVI, two-dimensional echocardiography is probably highly sensitive and specific for the diagnosis of RVI, by detecting RV wall motion and thickening abnormalities. Due to advantages, such as noninvasivity and repeatibility, two-dimensional echocardiography can be used in the selection of patients who deserve hemodynamic monitoring and in follow-up studies.     

Right ventricular strain and strain rate properties in patients with right ventricular myocardial infarction

BACKGROUND: This study was planned to assess strain and strain rate properties of right ventricle in patients with RV myocardial infarction. MATERIAL AND METHOD: 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. RESULTS: 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. CONCLUSION: 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.     

Left ventricular pseudoaneurysm complicating inferior myocardial infarction: a case report

Acquired pseudoaneurysm of the left ventricle is a very rare disorder and mostly occurs after large transmural myocardial infarction (MI) with peak creatine phosphokinase-MB levels greater than 150 IU/mL. Patients developing left ventricular (LV) pseudoaneurysm usually present with angina or heart failure symptoms. Although different imaging modalities exist, coronary angiography is the gold standard for diagnosis. Surgery is the treatment of choice for LV pseudoaneurysms detected in the first months after MI. Here we report the case of a 74-year-old woman who presented with a relatively small inferior MI due to right coronary artery occlusion and complicated by LV pseudoaneurysm.     

The Diagnostic Value of 12‐Lead Electrocardiogram in Predicting Infarct‐Related Artery and Right Ventricular Involvement in Acute Inferior Myocardial Infarction

Background: The aim of the present study was to investigate the predictive value of presentation and 24‐hour electrocardiograms in defining the infarct‐related artery (IRA), its lesion segment, and the right ventricular involvement in acute inferior myocardial infarction (Ml). Methods: One hundred forty‐nine patients with acute inferior MI were included. Infarct‐related artery, its lesion segment, and the validity of new ECG criteria for the diagnosis of right ventricular Ml (RVMI) were investigated by means of criteria obtained from admission and 24‐hour ECGs. Results: The presence of ST‐segment elevation in lead III > lead II criterion (Criterion 1) and ST‐segment depression in lead I > lead aVL criterion (Criterion 2) from admission ECG defined the right coronary artery (RCA) as IRA with a sensitivity of 64% and a specificity of 100%. These two criteria also defined the proximal or mid lesions in RCA as culprit lesions (sensitivity of 99%, specificity of 96%). Absence of these two criteria indicated Cx as IRA with a sensitivity of 50% and a specificity of 97%. The depth of Q wave in lead III > lead II criterion (Criterion 3) had no value for discrimination of IRA, but the width of Q wave in lead III > lead II criterion (Criterion 4) supported the RCA to be IRA with a sensitivity of 60% and a specificity of 61% (Criteria 3 and 4 were obtained from 24‐hour ECGs). The finding of Criterion 1 plus Criterion 5 (ST elevation in V₁ but no ST elevation in V2) on admission ECG had a sensitivity of 63% and a specificity of 99% in the diagnosis of RVMI. Conclusion: We concluded that 12‐lead ECG is a cheap, easy, and readily obtainable diagnostic approach in discrimination of IRA and its culprit lesion segment. However, despite high specificity, due to moderate degree sensitivity, its value for the diagnosis of RVMI is questionable. A.N.E. 2001; 6(3):229–235     

Severity of residual stenosis of infarct-related lesion and left ventricular function after single-vessel anterior wall myocardial infarction: implication of ST-segment elevation in lead aVL of the admission electrocardiograms

BACKGROUND: The relationship between the severity of chronic-phase stenosis of infarct-related lesions (IRLs) and chronic left ventricular function in anterior acute myocardial infarctions (AMI) has not been adequately investigated. HYPOTHESIS: This study investigated whether ST elevation in lead aVL of admission electrocardiogram (ECG) would be a determinant factor of the relationship between the severity of stenosis of the IRL and chronic left ventricular function after anterior wall AMI. METHODS: One month after AMI, the IRL was evaluated by coronary angiography in 98 patients with anterior AMI, and left ventricular ejection fraction (LVEF) was determined using multigated radionuclide angiocardiography. Patients were classified according to the severity of the IRL: patients with 100% occlusion (Group O), patients with 90 to 99% stenosis (Group H), and patients with < or =75% stenosis (Group L). Patients with ST elevation > or =0.1 mV in the aVL lead on their admission ECG were included in the ST-elevation group, and those with ST elevation <0.1 mV were included in the non-ST-elevation group. RESULTS: The LVEF was greater in the non-ST-elevation group than in the ST-elevation group (p<0.0001), and the LVEF in a whole group as follows: Group L LVEF>Group H LVEF>Group O LVEF (p = 0.0160). In the ST-elevation group, LVEF was higher in Group L than in the other groups (p = 0.0251). There were three independent predictors of a reduced LVEF: ST-elevation in aVL [odds ratio (OR): 3.38, p = 0.0044], IRL stenosis > or =90% (OR: 2.90, p = 0.0044), and the IRL occurring in the left anterior descending artery proximal to the first diagonal branch (OR: 6.31, p = 0.0024). CONCLUSION: Left ventricular function was preserved, regardless of the severity of residual stenosis, in patients without ST elevation in aVL if the IRL was not totally occluded. In patients with ST elevation in aVL, LVEF was lower in patients with more severe stenosis, even if the IRL was patent.     

Right Ventricular Infarction Mimicking Anterior Infarction

It is rare to observe ST elevation in anterior derivations caused by right ventricular branch occlusion. We described the case of a patient with unstable angina who developed acute right ventricular myocardial infarction with ST‐segment elevation in anterior precordial leads (V₁–V₄) shortly after coronary angiography. Coronary angiogram revealed total occlusion of the right coronary artery (RCA) proximally to the right ventricular branch. This reminds us that the presence of diffuse ST‐segment elevation in the precordial leads could be due to acute RCA occlusion. The differentiation of these two entities is important, as their therapies are quite different.     

Right ventricular ischemia mimicking acute anterior myocardial infarction.

Isolated right ventricular ischemia in combination with myocardial infarction (MI) is uncommon, accounting for fewer than 3% of all MI cases. A young man who presented with acute right ventricular ischemia from occlusion of a codominant right coronary artery proximal to an acute marginal branch is presented. His presenting electrocardiogram (ECG) showed ST segment elevation in V1 to V4 mimicking acute anterior MI. ECG criteria for isolated right ventricular ischemia are discussed.     

High-resolution and signal-averaged electrocardiography to separate post-myocardial infarction patients with and without ventricular tachycardia

High-resolution and signal-averaged ECG, 24 h Holter recordingand ejection fraction were used to separate post-myocardialinfarction patients with and without ventricular tachycardia(VT) among 150 individuals: 26 patients with an old myocardialinfarction and documented sustained VT, 104 patients with anacute myocardial infarction without sustained VT, who were followed-upfor 2 years, and 20 healthy volunteers. Bipolar orthogonal XYZleads were recorded, high-pass filtered at cut-off frequenciesof 25, 40, 60, 80 and 100 Hz, and combined to vector magnitudex² + Y²+ Z². The filtered QRS duration, the root-mean-squarevoltages of different time intervals and the durations of lowamplitude signals under different thresholds, both from theinitial and terminal QRS, were calculated. The sensitivity andspecificity of each parameter alone and in every combinationof two, three and four parameters (17 million different combinations)were computed both from non-averaged and averaged data. Thebest separation was achieved by 12 combinations all includingfour signal-averaged ECG parameters, with a sensitivity of 81%and a specificity of 79%. The parameters represented most were:filtered QRS duration at 25 Hz, RMS voltage of the last 50 msat 25 Hz, terminal LAS duration at 80 Hz, and RMS voltage ofthe last 20 ms at 80 Hz. Parameters of the initial QRS complexdid not improve either the sensitivity or the specificity ofthe method. In logistic regression analysis, the best combinationsof four signal-averaged ECG parameters separated VT patientsbetter (P<0·001) than non-sustained ventricular tachycardiaat Holter (P=0·001); left ventricular ejection fraction(P=0·01) or age (P=0·006). Parameters calculatedfrom averaged data gave better results than parameters calculatedfrom non-averaged data.     

Vectorcardiographic criteria for acute right ventricular infarction

Based on serial vectorcardiographic and cardiac scintigraphicstudies of 62 patients with acute myocardial infarction, wepropose vectorcardiographic criteria for the diagnosis of acuteright ventricular infarction. These criteria are: (1) the directionof the maximal spatial ST vector points either to the right-anterior-inferioror to the right-posterior–inferior octant, and (2) themagnitude of the projection of the maximal spatial ST vectoris 0.15 mV in the horizontal plane. By using these criteriacorrelated with scintigraphic results, 92% sensitivity was achievedtogether with 98% specificity; the Kappa statistic was 0.90.In patients with acute inferior and right ventricular infarction,the serial maximal spatial ST vector swung to-and-fro like a‘tug of war’ between right-anterior-inferior andright-posterior-inferior octants during the acute stage. Inpatients with acute inferior-posterior and right ventricularinfarction, the serial maximal spatial ST vector pointed tothe right-posterior-inferior octant during the whole courseof the acute stage. Failure to recognize this electrical phenomenonmay make the clinician inaccurate when judging the clinicalcourse of acute right ventricular infarction or over-estimatethe result of therapeutic intervention.     

Right ventricular myocardial infarction: From pathophysiology to prognosis

Right ventricle myocardial infarctions (RVMIs) accompany inferior wall ischemia in up to one-half of cases. The clinical sequelae of RVMIs vary from no hemodynamic compromise to severe hypotension and cardiogenic shock. Diagnosis is based on physical examination, electrocardiography, echocardiography and coronary angiography. Because the standard 12-lead electrocardiogram is insufficient for the assessment of RV involvement, right-sided precordial leads should always be included. Adequate fluid administration in combination with positive inotropic agents and early coronary reperfusion are crucial components of treatment, while diuretics and nitrates should be avoided. Intra-aortic balloon counterpulsation and right ventricle assist devices may be used with success in RVMIs associated with medically refractory heart failure. Right ventricular involvement appears to be an independent prognostic factor that dramatically increases in-hospital mortality, due, in part, to a significantly higher risk of hemodynamically compromising arrhythmias. Thus, using right-sided precordial leads and early RVMI identification to trigger an appropriately aggressive treatment protocol may improve patients’ prognosis.