Right ventricular involvement in acute left ventricular myocardial infarction: prognostic implications of MRI findings. AJR Am J Roentgenol. 2010;194:592-598. [PMID: 20173133 DOI: 10.2214/ajr.09.2829]

Right Ventricular Myocardial Infarction: Pathophysiology, Diagnosis, and Therapeutic Approaches

Right ventricular myocardial infarction (RVMI) is a significant and distinct form of acute myocardial infarction associated with considerable morbidity and mortality. It occurs most commonly due to proximal right coronary artery obstruction, often in conjunction with inferior myocardial infarction. RVMI poses unique diagnostic and therapeutic challenges due to the anatomical and functional differences between the right and left ventricles. Key clinical manifestations include symptoms of right-sided heart failure, such as hypotension, jugular venous distention, and peripheral edema. The pathophysiology of RVMI involves impaired right ventricular (RV) function, decreased cardiac output, and poor hemodynamic stability, often leading to cardiogenic shock. Diagnostic tools, including 12-lead electrocardiography, echocardiography, cardiac magnetic resonance imaging, and coronary angiography, play crucial roles in detecting RVMI and determining its severity. Treatment strategies focus on early revascularization through primary percutaneous coronary intervention or thrombolysis, maintaining adequate RV preload, and managing arrhythmias and hemodynamic instability. In severe cases, mechanical circulatory support, such as intra-aortic balloon pumps and extracorporeal membrane oxygenation, may be required. Despite advancements in imaging and therapeutic approaches, RVMI remains a complex condition that demands timely and specialized management to improve patient outcomes. Further research is needed to refine diagnostic and treatment strategies and to reduce the high mortality rates associated with this condition.

Acute epigastric pain unveiling biventricular myocardial infarction: A case report

Acute coronary syndromes are a clinical entity frequently encountered in practice and are responsible for significant morbidity and mortality, despite therapeutic advances. The initiation of early reperfusion therapy reduces mortality and morbidity and improves patients' prognosis, but this depends on how quickly patients receive their treatment. Although it is often easy to diagnose in the presence of typical symptoms, certain patients, such as diabetics, sometimes have atypical symptoms, resulting in a delay in management. In nearly 50% of cases, inferior wall ischaemia is accompanied by right ventricular myocardial infarction; the clinical outcomes range from no hemodynamic compromise to severe hypotension and cardiogenic shock. In this article, we present the case of a 54-year-old male patient with active smoking and poorly controlled type 2 diabetes as cardiovascular risk factors who initially consulted at the first hour for epigastric pain, for which he received symptomatic treatment. As the symptoms persisted, he was admitted to our department at the eighth hour, where he was diagnosed with a biventricular infarction.

Two-Dimensional Transthoracic Echocardiography-Based Diagnosis of Right Ventricular Aneurysm: A Neglected Issue in Patients with Coronary Artery Disease: Case Series and Literature Review

Right ventricular (RV) aneurysm is a very rare ventricular lesion. An aneurysm is formed mainly as a complication of myocardial infarction (MI). As an RV aneurysm is a potentially life-threatening occurrence, its appropriate diagnosis is of great significance. However, right-sided heart diseases, especially RV aneurysms, have been neglected for years. Recent studies in the literature have elucidated the role of the right side of the heart in patients' prognosis and response to treatment. However, RV aneurysm has been scarcely investigated, and most of the attention has been given to the left ventricular aneurysm in patients with ischemic heart diseases (IHD). Herein, we investigated a total of 625 patients with IHD referred for two-dimensional transthoracic echocardiography (2D TTE), among whom 18 were diagnosed with RV aneurysms through precise examination of several TTE views. The characteristics of these cases, including demographics, medical history, and results of cardiac tests (which the patients underwent previously), were recorded and presented. This study emphasized the importance of performing a meticulous 2D TTE evaluation and a thorough examination of different views by an expert echocardiographer, with special attention to the presence of an RV aneurysm in a patient suffering from IHD who presented either with acute coronary syndrome, including MI, or chronic IHD. The scarcity of information, especially in terms of complications and the most appropriate diagnostic methods, calls for further studies in this regard.

The Incidence and Impact of Permanent Right Ventricular Infarction on Left Ventricular Infarct Size in Patients With Inferior ST-Segment Elevation Myocardial Infarction

Mounting evidence shows that right ventricle (RV) function carries independent prognostic influence in various disease states. This study aimed to investigate the incidence and impact of permanent RV infarction in patients with inferior ST-segment elevation myocardial infarction (STEMI) and culprit lesion in the right coronary artery (RCA). In this substudy of the DANAMI-3 (DANish Study of Optimal Acute Treatment of Patients with ST-segment Elevation Myocardial Infarction) trial, cardiac magnetic resonance was performed in 291 patients at day 1 and follow-up 3 months after primary percutaneous coronary intervention of 674 patients with STEMI with the culprit lesion in the RCA. Final infarct was assessed using late gadolinium enhancement on cardiac magnetic resonance at 3 months. Patients with permanent RV infarction (20%) had lower ventricular function at follow-up; RV ejection fraction (EF) 47% ±6 versus 50% ± 5 (p <0.005) and left ventricular (LV) EF 56% ± 8 versus 60% ± 9 (p <0.006). Furthermore, patients with permanent RV infarction had a higher incidence of microvascular obstruction 39 (67%) versus 81 (39%) (p <0.001), larger final LV infarct size 16% ±8 versus 10% ± 8 (p <0.001) and larger LV area at risk 33% ± 10 versus 29% ± 9 (p <0.001). Permanent RV infarction was an independent predictor of final LV infarct size (p <0.001) but was not associated with LVEF (β = -0.0; p = 0.13) in multivariable analyses. In conclusion, permanent RV infarction was seen in 20% of patients with inferior STEMI and culprit lesion in RCA and independently predicted final LV infarct size. However, permanent RV infarction did not predict overall LV function. LGE was used to detect infarct location and quantify infarct size.¹⁷ LGE in RV free wall on follow-up CMR was considered as permanent infarction. LGE images were obtained 10 minutes after intravenous injection of 0.1-mmol/kg body weight of gadolinium-based contrast (Gadovist; Bayer Schering, Berlin, Germany) using an electrocardiogram (ECG)-triggered inversion-recovery sequence. The inversion time was adjusted to null the signal from the normal myocardium. Short-axis images were acquired from the atrioventricular plane to the apex with adjacent 8-mm slices. The remaining protocol has been described previously.¹⁶.

RIGHT VENTRICLE FUNCTION IN PATIENTS WITH ANTERIOR MYOCARDIAL INFARCTION: ARE WE SURE IT IS NOT INVOLVED?

The right and left ventricle of heart are intimately connected by anatomical and functional links. Hence, acute changes in cardiac geometry and function can modify the performance and physiology of both sides of the heart, influencing each other. After a brief overview of the anatomy and related imaging techniques for the study of right ventricular function, we report a review on the interesting correlation of acute anterior myocardial infarction and right ventricular function, very often underestimated.

Cardiac MRI in Patients with Acute Chest Pain

Acute chest pain is a common reason for visits to the emergency department. It is important to distinguish among the various causes of acute chest pain, because treatment and prognosis are substantially different among the various conditions. It is critical to exclude acute coronary syndrome (ACS), which is a major cause of hospitalization, death, and health care costs worldwide. Myocardial ischemia is defined as potential myocyte death secondary to an imbalance between oxygen supply and demand due to obstruction of an epicardial coronary artery. Unobstructed coronary artery disease can have cardiac causes (eg, myocarditis, myocardial infarction with nonobstructed coronary arteries, and Takotsubo cardiomyopathy), and noncardiac diseases can manifest with acute chest pain and increased serum cardiac biomarker levels. In the emergency department, cardiac MRI may aid in the identification of patients with non-ST-segment elevation myocardial infarction or unstable angina or ACS with unobstructed coronary artery disease, if the patient's clinical history is known to be atypical. Also, cardiac MRI is excellent for risk stratification of patients for adverse left ventricular remodeling or major adverse cardiac events. Cardiac MRI should be performed early in the course of the disease (<2 weeks after onset of symptoms). Steady-state free-precession T2-weighted MRI with late gadolinium enhancement is the mainstay of the cardiac MRI protocol. Further sequences can be used to analyze the different pathophysiologic subjacent mechanisms of the disease, such as microvascular obstruction or intramyocardial hemorrhage. Finally, cardiac MRI may provide several prognostic biomarkers that help in follow-up of these patients. Online supplemental material is available for this article. ^©RSNA, 2020.

Multimodality imaging in takotsubo syndrome: a joint consensus document of the European Association of Cardiovascular Imaging (EACVI) and the Japanese Society of Echocardiography (JSE)

Takotsubo syndrome (TTS) is a complex and still poorly recognized heart disease with a wide spectrum of possible clinical presentations. Despite its reversibility, it is associated with serious adverse in-hospital events and high complication rates during follow-up. Multimodality imaging is helpful for establishing the diagnosis, guiding therapy, and stratifying prognosis of TTS patients in both the acute and post-acute phase. Echocardiography plays a key role, particularly in the acute care setting, allowing for the assessment of left ventricular (LV) systolic and diastolic function and the identification of the typical apical-midventricular ballooning pattern, as well as the circumferential pattern of wall motion abnormalities. It is also useful in the early detection of complications (i.e. LV outflow tract obstruction, mitral regurgitation, right ventricular involvement, LV thrombi, and pericardial effusion) and monitoring of systolic function recovery. Left ventriculography allows the evaluation of LV function and morphology, identifying the typical TTS patterns when echocardiography is not available or wall motion abnormalities cannot be properly assessed with ultrasound. Cardiac magnetic resonance provides a more comprehensive depiction of cardiac morphology and function and tissue characterization and offers additional value to other imaging modalities for differential diagnosis (myocardial infarction and myocarditis). Coronary computed tomography angiography has a substantial role in the diagnostic workup of patients with acute chest pain and a doubtful TTS diagnosis to rule out other medical conditions. It can be considered as a non-invasive appropriate alternative to coronary angiography in several clinical scenarios. Although the role of nuclear imaging in TTS has not yet been well established, the combination of perfusion and metabolic imaging may provide useful information on myocardial function in both the acute and post-acute phase.

Multimodality imaging in takotsubo syndrome: a joint consensus document of the European Association of Cardiovascular Imaging (EACVI) and the Japanese Society of Echocardiography (JSE)

Takotsubo syndrome (TTS) is a complex and still poorly recognized heart disease with a wide spectrum of possible clinical presentations. Despite its reversibility, it is associated with serious adverse in-hospital events and high complication rates during follow-up. Multimodality imaging is helpful for establishing the diagnosis, guiding therapy, and stratifying prognosis of TTS patients in both the acute and post-acute phase. Echocardiography plays a key role, particularly in the acute care setting, allowing for the assessment of left ventricular (LV) systolic and diastolic function and the identification of the typical apical-midventricular ballooning pattern, as well as the circumferential pattern of wall motion abnormalities. It is also useful in the early detection of complications (i.e. LV outflow tract obstruction, mitral regurgitation, right ventricular involvement, LV thrombi, and pericardial effusion) and monitoring of systolic function recovery. Left ventriculography allows the evaluation of LV function and morphology, identifying the typical TTS patterns when echocardiography is not available or wall motion abnormalities cannot be properly assessed with ultrasound. Cardiac magnetic resonance provides a more comprehensive depiction of cardiac morphology and function and tissue characterization and offers additional value to other imaging modalities for differential diagnosis (myocardial infarction and myocarditis). Coronary computed tomography angiography has a substantial role in the diagnostic workup of patients with acute chest pain and a doubtful TTS diagnosis to rule out other medical conditions. It can be considered as a non-invasive appropriate alternative to coronary angiography in several clinical scenarios. Although the role of nuclear imaging in TTS has not yet been well established, the combination of perfusion and metabolic imaging may provide useful information on myocardial function in both the acute and post-acute phase.

Short-term prognostic value of TAPSE, RVFAC and Tricuspid S' wave peak systolic velocity after first acute myocardial infarction

Objectives

Right ventricular dysfunction impacts the prognosis of various heart diseases. We set-out to examine which right ventricular functional parameters after STEMI and NSTEMI have prognostic value. Of 297 eligible participants, 266 (149 STEMI and 117 NSTEMI) completed follow-up. All patients underwent Grace score and 2D-echocardiography within 24 h. Outcome was defined as occurrence of Major Adverse Cardiovascular events (MACE), such as death, recurrent ischaemia, arrhythmia, reinfarction, stroke or heart failure, within 30 days. Patients were categorized into patients with MACE and patients without MACE.

Results

In STEMI-patients, compared to those without MACE, patients with MACE experienced higher grace score, left ventricle (LV) end-systolic volume, LV end-systolic dimension and wall motion score index values, but lower tricuspid annular plane systolic excursion, right ventricle (RV) fractional area change, Tricuspid S’ wave peak systolic velocity and LV ejection fraction. Nevertheless, in NSTEMI-patients, those with MACE exhibited higher left atrial volume index values, but lower tricuspid annular plane systolic excursion, RV fractional area change, S’ wave peak systolic velocity and LVEF. Right ventricular fractional area change < 37.5%, tricuspid annular plane systolic excursion < 15.8 mm and Tricuspid S’ peak systolic velocity < 9.67 cm/s are independent predictors of MACE within first 30 days after STEMI and NSTEMI.

QRS-T-angle in Patients with ST-Segment Elevation Myocardial Infarction (STEMI) - a Comparison with Cardiac Magnetic Resonance Imaging

Background: The QRS-T angle from the surface EKG is a promising prognostic marker in patients with coronary artery disease. Cardiovascular magnetic resonance (CMR) imaging with late gadolinium enhancement (LGE) offers high resolution imaging of myocardial damage. We investigated the association of the QRS-T angle and the extent of myocardial damage as assessed by LGE in patients with acute ST-segment myocardial infarction (STEMI) Methods: 169 patients with STEMI obtained a standardized digital 12-lead EKG on admission for the calculation of the QRS-T angle and underwent CMR imaging for analysis of infarct size by LGE within the first week. Patients were divided into groups: (1) abnormal QRS-T angle ≥ 90 degree and (2) QRS-T angle < 90 degree. Results: Patients with a QRS-T angle of 90 degree or more had larger infarcts (36.5±12.4 vs. 13.3±9.5; p<0.001) and lower ejection fraction (42.9±12.1% vs. 50.6±10.6%; p<0.001). Conclusion: The extent of myocardial damage as measured by the gold standard LGE is associated with a larger QRS-T angle calculated from the surface EKG.

Assessment of right ventricular function after successful revascularization for acute anterior myocardial infarction without right ventricular infarction by echocardiography

BACKGROUND

Right ventricular (RV) involvement in acute left ventricular (LV) myocardial infarction (MI) is frequently underestimated in the clinical setting owing to the diagnostic limitations of the electrocardiogram and echocardiography.

OBJECTIVE

To assess RV function in patients presented with first acute anterior ST elevation myocardial infarction (STEMI) who underwent successful primary percutaneous coronary intervention (PCI) and factors affecting it.

METHODS

Forty consecutive patients with anterior STEMI who underwent successful primary PCI were enrolled in the study. Presence of a coexisting clinical condition that might affect RV function, patients with RV infarction or those having significant stenosis (>50%) affecting RV branch or right coronary artery proximal to RV branch were excluded. Echocardiography was performed during the hospital stay to assess the LV and RV systolic and diastolic function with special focus on tricuspid annular plane systolic excursion, RV end-diastolic dimension, right atrial area, RV fractional area change, and tissue Doppler-derived myocardial performance index.

RESULTS AND CONCLUSION

RV dysfunction according to our definition in the first anterior MI occurred in (55%) of the study population. Independent predictors for abnormal RV function were left circumflex artery mid or proximal affection, eventful procedure, occurrence of no reflow, glucose level, LV end-systolic dimension, LV end-diastolic dimension, and LV ejection fraction.

Prognostic significance of electrocardiographic right ventricular hypertrophy in the general population

BACKGROUND

Echocardiographically detected right ventricular hypertrophy (RVH) is associated with cardiovascular disease (CVD) and mortality. However, the prognostic significance of electrocardiographic (ECG)RVH criteria as predictors of poor outcomes in the general population is unclear.

METHODS

This study included 7857 participants (59.8 ± 13.4 years, 52.6% women) from the Third National Health and Nutrition Examination Survey. Sixteen different ECG-RVH criteria were created from digitally recorded and centrally processed electrocardiograms. All-cause mortality was ascertained using the National Death Index. Cox proportional hazards analysis was used to examine the association between baseline ECG-RVH criteria and all-cause mortality.

RESULTS

The prevalence of RVH varied widely among the criteria. The lowest ECG-RVH prevalence was 0.09% (using S > R in I, II, III) while the highest prevalence was 20.7% (using (R I + S III) - (S I + R III) < 15 mm). During a median follow-up of 14 years, 2812 deaths occurred. The mortality rate was highest among participants with ECG-RVH defined as R:S ratio V₅ < 0.75. In multivariable adjusted models, 9 out of the 16 ECG-RVH criteria were significantly associated with all-cause mortality. When ECG-RVH was defined as the presence of any ECG-RVH criteria, each additional ECG-RVH criteria was associated with 6% increased risk of all-cause mortality (HR (95% CI):1.06(1.03,1.10)).

CONCLUSIONS

There is a wide variation in the prevalence of ECG-RVH when different criteria are applied in the general population. However, the presence of ECG-RVH by most criteria regardless of prevalence was associated with poor prognosis suggesting that appropriate choice of criteria may enhance the utilization of these ECG markers in risk stratification.

Right ventricular function in patients presenting with non-ST-segment elevation myocardial infarction undergoing an invasive approach

Background

Right ventricular involvement in ST segment elevation myocardial infarction (STEMI) entails an increased morbidity and mortality. However, very scarce data is present on its affection in the setting of non-ST segment elevation myocardial infarction (NSTEMI).

Aim

To assess the affection of right ventricular function in patients presenting with NSTEMI undergoing an invasive procedure.

Subjects and methods

One hundred and fifty patients admitted with a first NSTEMI and eligible for reperfusion therapy via invasive percutaneous coronary intervention. These patients were divided in two groups; group A including patients with normal RV function, and group B including patients with impaired RV function as diagnosed by tricuspid annular plane systolic excursion (TAPSE) cutoff value < 17 mm. All patients underwent angioplasty and were followed up in-hospital and for 3 months.

Results

RV dysfunction occurred in ninety-five (61.3%) patients of the study population. Significant improvement occurred to TAPSE after 3 months in comparison to TAPSE at baseline (15.45 ± 3.21 versus 17.09 ± 4.17 mm). Those with impaired RV function showed improvement of TAPSE after three months as compared to baseline (13.62 ± 2.58 vs 17.16 ± 3.64 p = 0.008). Multivariate analysis determined the independent predictors of RV dysfunction as RVEDD > 26 mm, RVFAC < 35%, RAA > 20 cm², and TAPSE < 17 mm.

Conclusion

RV dysfunction is not uncommon in NSTEMI when using the definition of TAPSE < 17 mm. Following up RV function by TAPSE, showed significant improvement after 3 months with successful PCI as compared to baseline. We recommend assessing and following up RV function in all patients admitted with a NSTEMI.

Acute right ventricular myocardial infarction

INTRODUCTION

Acute right ventricular myocardial infarction (RVMI) is observed in 30-50% of patients presenting with inferior wall myocardial infarction (MI) and, occasionally, with anterior wall MI. The clinical consequences vary from no hemodynamic compromise to severe hypotension and cardiogenic shock depending on the extent of RV ischemia. Areas covered: The pathophysiological mechanisms, diagnostic steps, and novel therapeutic approaches of acute RVMI are described. Expert commentary: Diagnosis of acute RVMI is based on physical examination, cardiac biomarkers, electrocardiography, and coronary angiography, whereas noninvasive imaging modalities (echocardiography, cardiac magnetic resonance imaging) play a complementary role. Early revascularization, percutaneous or pharmacological, represents key step in the management of RMVI. Maintenance of reasonable heart rate and atrioventricular synchrony is essential to sustain adequate cardiac output in these patients. When conventional treatment is not successful, mechanical circulatory support, including right ventricle assist devices, percutaneous cardiopulmonary support, and intra-aortic balloon pump, might be considered. The prognosis associated with RVMI is worse in the short term, compared to non-RVMI, but those patients who survive hospitalization have a relatively good long-term prognosis.

The impact of right ventricular function assessed by 2-dimensional speckle tracking echocardiography on early mortality in patients with inferior myocardial infarction

BACKGROUND

Right ventricular (RV) involvement in inferior myocardial infarction (MI) increases in-hospital morbidity and mortality.

HYPOTHESIS

RV systolic dysfunction assessed by 2-dimensional speckle tracking echocardiography (STE) might be a predictor of early mortality in patients with acute inferior MI.

METHODS

Eighty-one consecutive patients with acute inferior MI (mean age, 60.8 ± 12.7 years; 18 females) were included. RV myocardial involvement was defined as an elevation >1 mm in V₁ or V₄ R within 12 hours of symptom onset. RV function was assessed by STE. Patients were followed for 30 days for all-cause mortality.

RESULTS

Thirty-eight patients had RV myocardial involvement, and they had significantly lower tricuspid annular plane systolic excursion (TAPSE), tricuspid annular systolic velocity (RVS), and left ventricular (LV) and RV global longitudinal strain (GLS). Nine patients (11%) died within 30 days. The mean age of mortality group was higher with more female frequency. They had significantly higher pro-BNP, hs-troponin T, and creatinine levels, but lower hemoglobin levels. TIMI 3 flow was significantly less achieved in mortality group. RV myocardial involvement was more frequent in the mortality group, and they had significantly lower TAPSE, RVS, and LV and RV GLS. Multivariate analysis revealed that age and RV GLS were independent predictors of early mortality. RV GLS ≤ -14% predicted early mortality in patients with acute inferior MI with a sensitivity of 88.9% and a specificity of 62.5% (AUC: 0.817, P = 0.002).

CONCLUSIONS

RV GLS may be useful in predicting early mortality in patients with acute inferior MI.

The Dark Side of the Moon: The Right Ventricle

The aim of this review article is to summarize current knowledge of the pathophysiology underlying right ventricular failure (RVF), focusing, in particular, on right ventricular assessment and prognosis. The right ventricle (RV) can tolerate volume overload well, but is not able to sustain pressure overload. Right ventricular hypertrophy (RVH), as a response to increased afterload, can be adaptive or maladaptive. The easiest and most common way to assess the RV is by two-dimensional (2D) trans-thoracic echocardiography measuring surrogate indexes, such as tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and tissue Doppler velocity of the lateral aspect of the tricuspid valvular plane. However, both volumes and function are better estimated by 3D echocardiography and cardiac magnetic resonance (CMR). The prognostic role of the RV in heart failure (HF), pulmonary hypertension (PH), acute myocardial infarction (AMI), and cardiac surgery has been overlooked for many years. However, several recent studies have placed much greater importance on the RV in prognostic assessments. In conclusion, RV dimensions and function should be routinely assessed in cardiovascular disease, as RVF has a significant impact on disease prognosis. In the presence of RVF, different therapeutic approaches, either pharmacological or surgical, may be beneficial.

Clinical predictors for the manifestation of late gadolinium enhancement after acute myocardial infarction

Despite prompt revascularization, some patients with acute myocardial infarction (AMI) develop myocardial scars, which can be visualized by late gadolinium enhancement (LGE) in cardiovascular magnetic resonance imaging (CMR). Our goal was to identify angiographic findings that were predictive for scar development in patients after reperfused AMI.We examined 136 patients after first ST-elevated myocardial infarction by CMR after a median of 4 days (range: 2-7). Patients with manifestation of LGE were matched to patients without LGE by means of age and gender. Clinical follow-up with a combined primary endpoint including myocardial reinfarction, congestive heart failure, stroke, death and development of left ventricular thrombus was reported after 24 months.Patients with manifestation of LGE had a significant longer time of symptom-to-intervention, a higher prevalence of anterior AMI, and more proximal culprit lesions. Furthermore, left ventricular ejection fraction was significantly decreased, and peak values of infarct markers were significantly higher in these patients. Preinterventional thrombolysis in myocardial infarction-0-flow was significantly more frequent in patients with LGE manifestation. The presence of 3-vessel disease (odds ratio 53.99, 95% confidence interval 8.22-354.63, P <.001), a proximal culprit lesion, and high creatine kinase myocardial band (CK-MB) values were identified as independent predictors of LGE. Follow-up demonstrated a higher incidence of clinical events in the group with LGE, with the most common cause of heart failure (38.2% vs 7.4%, P <.001).The extent of angiographic findings in AMI plays a major role in the manifestation of LGE. The presence of a multivessel disease, a proximal culprit lesion, and high values of CK-MB are strong independent predictors for LGE manifestation.

Role of cardiovascular magnetic resonance in acute and chronic ischemic heart disease

Cardiovascular magnetic resonance (CMR) is a multi-parametric, multi-planar, non-invasive imaging technique, which allows accurate determination of biventricular function and precise myocardial tissue characterization in a one-stop-shop technique, free from the use of ionizing radiations. Though CMR has been increasingly applied over the last two decades in every-day clinical practice, its widest application has been in the assessment of ischemic cardiomyopathy.

Cardiovascular magnetic resonance imaging assessment of outcomes in acute myocardial infarction

Cardiovascular magnetic resonance (CMR) imaging uniquely characterizes myocardial and microvascular injury in acute myocardial infarction (AMI), providing powerful surrogate markers of outcomes. The last 10 years have seen an exponential increase in AMI studies utilizing CMR based endpoints. This article provides a contemporary, comprehensive review of the powerful role of CMR imaging in the assessment of outcomes in AMI. The theory, assessment techniques, chronology, importance in predicting left ventricular function and remodelling, and prognostic value of each CMR surrogate marker is described in detail. Major studies illustrating the importance of the markers are summarized, providing an up to date review of the literature base in CMR imaging in AMI.

Right Ventricular Function After Acute Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention (from the Glycometabolic Intervention as Adjunct to Primary Percutaneous Coronary Intervention in ST-Segment Elevation Myocardial Infarction III Trial)

Right ventricular (RV) dysfunction is a powerful risk marker after acute myocardial infarction (MI). Primary percutaneous coronary intervention (PCI) has markedly reduced myocardial damage of the left ventricle, but reliable data on RV damage using cardiac magnetic resonance imaging (MRI) are scarce. In a recent trial of patients with acute MI treated with primary PCI, in which the primary end point was left ventricular (LV) ejection fraction after 4 months measured with MRI, we conducted a prospectively defined substudy in which we examined RV function. RV ejection fraction (RVEF) and RV scar size were measured with MRI at 4 months. Tricuspid annular plane systolic excursion (TAPSE) and RV free wall longitudinal strain (FWLS) were assessed using echocardiography before discharge and at 4 months. We studied 258 patients without diabetes mellitus; their mean age was 58 ± 11 years, 79% men and mean LV ejection fraction was 54 ± 8%. Before discharge, 5.2% of patients had TAPSE <17 mm, 32% had FWLS > -20% and 11% had FWLS > -15%. During 4 months, TAPSE increased from 22.8 ± 3.6 to 25.1 ± 3.9 mm (p <0.001) and FWLS increased from -22.6 ± 5.8 to -25.9 ± 4.7% (p <0.001). After 4 months, mean RVEF on MRI was 64.1 ± 5.2% and RV scar was detected in 5 patients (2%). There was no correlation between LV scar size and RVEF (p = 0.9), TAPSE (p = 0.1), or RV FWLS (p = 0.9). In conclusion, RV dysfunction is reversible in most patients and permanent RV ischemic injury is very uncommon 4 months after acute MI treated with primary PCI.

Acute Complications of Myocardial Infarction in the Current Era: Diagnosis and Management

Coronary heart disease is a major cause of mortality and morbidity worldwide. The incidence of mechanical complications of acute myocardial infarction (AMI) has gone down to less than 1% since the advent of percutaneous coronary intervention, but although mortality resulting from AMI has gone down in recent years, the burden remains high. Mechanical complications of AMI include cardiogenic shock, free wall rupture, ventricular septal rupture, acute mitral regurgitation, and right ventricular infarction. Detailed knowledge of the complications and their risk factors can help clinicians in making an early diagnosis. Prompt diagnosis with appropriate medical therapy and timely surgical intervention are necessary for favorable outcomes.

Angiographic result of index PCI determines the presence of right ventricular infarction in patients with acute inferior myocardial infarction

It is still a matter of debate which patients with acute inferior myocardial infarction are at increased risk of developing right ventricular (RV) myocardial infarction (RVMI). Cardiac magnetic resonance imaging (CMRI) with late enchancement (LE) is regarded as the gold standard for RVMI assessment. We aimed to determine the impact of initial angiographic status and salutary effect of primary percutaneous coronary intervention (PCI) on the presence of RVMI. In 114 patients undergoing emergency angiography and primary PCI of right coronary artery, 3-5 days after index PCI, LE CMRI was performed for assessing the RVMI. Forty-eight patients (42%) demonstrated RVMI. Multivariate regression analysis identified TIMI flow <2 in at least one RV branch after PCI as an independent angiographic predictor of RVMI [odds ratio (OR) 143.00, 95% confidence interval (CI) 18.10-1130.05, p < 0.001]. ST-segment elevation ≥ 1 mm in V4R was present in 83 (73%). TIMI flow <3 in at least one RV branch before PCI (OR 4.07, 95% CI 1.24-13.33, p = 0.02) was independent angiographic predictor of ST-segment elevation ≥ 1 mm in V4R. The only predictor of RVMI was TIMI flow <2 in at least one RV branch after PCI. ST-segment elevation ≥ 1 mm in V4R is caused by TIMI <3 flow in at least one RV branch before index PCI.

Usefulness of cardiac MRI in the prognosis and follow-up of ischemic heart disease

Cardiac magnetic resonance imaging (MRI) is an important tool that makes it possible to evaluate patients with cardiovascular disease; in addition to infarction and alterations in myocardial perfusion, cardiac MRI is useful for evaluating other phenomena such as microvascular obstruction and ischemia. The main prognostic factors in cardiac MRI are ventricular dysfunction, necrosis in late enhancement sequences, and ischemia in stress sequences. In acute myocardial infarction, cardiac MRI can evaluate the peri-infarct zone and quantify the size of the infarct. Furthermore, cardiac MRI's ability to detect and evaluate microvascular obstruction makes it a fundamental tool for establishing the prognosis of ischemic heart disease. In patients with chronic ischemic heart disease, cardiac MRI can detect ischemia induced by pharmacological stress and can diagnose infarcts that can be missed on other techniques.

Right ventricular dysfunction predisposes to inducible ventricular tachycardia at electrophysiology studies in patients with acute ST-segment-elevation myocardial infarction and reduced left ventricular ejection fraction

BACKGROUND

Inducible ventricular tachycardia (VT) is a strong predictor of spontaneous ventricular tachyarrhythmia following ST-segment-elevation myocardial infarction. Reduced left ventricular ejection fraction (EF) predisposes patients to inducible VT after ST-segment-elevation myocardial infarction. However, the role of right ventricular (RV) dysfunction in predisposing to inducible VT has not been described previously.

METHODS AND RESULTS

Consecutive patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention underwent predischarge radionuclide gated heart pool scan to assess ventricular EF. The study cohort included patients with reduced left ventricular EF (left ventricular EF ≤40%) who underwent electrophysiology study (n=220) in an attempt to induce VT. We defined RV dysfunction as RVEF ≤35%. The end point was sustained monomorphic VT (cycle length ≥200 ms). This was considered a positive study. No inducible arrhythmia, ventricular fibrillation, or flutter (cycle length <200 ms) was considered a negative study. Infarct region, infarct-related artery, male sex, and RVEF ≤35% were univariable predictors of positive test. After multivariable analysis, RVEF ≤35% had the strongest association as an independent predictor of inducible VT at electrophysiology study (P<0.001; odds ratio, 5.8; 95% confidence interval, 3.005-11.262).

CONCLUSIONS

RV dysfunction (RVEF ≤35%) predisposed to inducible VT at electrophysiology study in patients with impaired left ventricular EF (≤40%) after acute ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention.

The challenges in the management of right ventricular infarction

In recent years, right ventricular (RV) infarction seems to be underdiagnosed in most cases of acute myocardial ischaemia despite its frequent association with inferior-wall and, occasionally, anterior-wall myocardial infarction (MI). However, its initial management is drastically different from that of left ventricular MI, and studies have indicated that RV infarction remains associated with significant morbidity and mortality, even in the mechanical reperfusion era. The pathophysiology of RV infarction involves the interaction between the right and left ventricle (LV), and the mechanism has been clarified with the advent of diagnostic non-invasive modalities, such as echocardiography and cardiac magnetic resonance. In recent years, considerable progress has been made in the treatment of RV infarction; early revascularization remains the cornerstone of the management, and fluid resuscitation, with appropriate target selection, is necessary to maintain appropriate preload. Early recognition in intensive care with clear understanding of the pathophysiology is essential to improve its prognosis. In terms of management, the support strategy for RV dysfunction is different from that for LV dysfunction since the former may often be temporary. Along with early reperfusion, maintenance of an adequate heart rate and atrioventricular synchrony are essential to sustain a sufficient cardiac output in patients with RV infarction. In refractory cases, more intensive mechanical support is required, and new therapeutic options, such as Tandem-Heart or percutaneous cardiopulmonary support systems, are being developed.

Cardiac magnetic resonance imaging findings and the risk of cardiovascular events in patients with recent myocardial infarction or suspected or known coronary artery disease: a systematic review of prognostic studies

The goal of this study was to review the prognostic value of cardiac magnetic resonance (CMR) imaging findings for future cardiovascular events in patients with a recent myocardial infarction (MI) and patients with suspected or known coronary artery disease (CAD). Although the diagnostic value of CMR findings is established, the independent prognostic association with future cardiovascular events remains largely unclear. Studies published by February 2013, identified by systematic MEDLINE and EMBASE searches, were reviewed for associations between CMR findings (left ventricular ejection fraction [LVEF], wall motion abnormalities [WMA], abnormal myocardial perfusion, microvascular obstruction, late gadolinium enhancement, edema, and intramyocardial hemorrhage) and hard events (all-cause mortality, cardiac death, cardiac transplantation, and MI) or major adverse cardiovascular events (MACE) (hard events and other cardiovascular events defined by the authors of the evaluated papers). Fifty-six studies (n = 25,497) were evaluated. For patients with recent MI, too few patients were evaluated to establish associations between CMR findings and hard events. LVEF (range of adjusted hazard ratios [HRs]: 1.03 to 1.05 per % decrease) was independently associated with MACE. In patients with suspected or known CAD, WMA (adjusted HRs: 1.87 to 2.99), inducible perfusion defects (adjusted HRs: 3.02 to 7.77), LVEF (adjusted HRs: 0.72 to 0.82 per 10% increase), and infarction (adjusted HRs: 2.82 to 9.43) were independently associated with hard events, and the presence of inducible perfusion defects was associated with MACE (adjusted HRs: 1.76 to 3.21). The independent predictor of future cardiovascular events for patients with a recent MI was LVEF, and the predictors for patients with suspected or known CAD were WMA, inducible perfusion defects, LVEF, and presence of infarction.

Primary reperfusion in acute right ventricular infarction: An observational study

AIM: To investigate the impact of primary reperfusion therapy (RT) on early and late mortality in acute right ventricular infarction (RVI).

METHODS: RVI patients (n = 679) were prospectively classified as without right ventricular failure (RVF) (class A, n = 425, 64%), with RVF (class B, n = 158, 24%) or with cardiogenic shock (CS) (class C, n = 96, 12%). Of the 679 patients, 148 (21.7%) were considered to be eligible for thrombolytic therapy (TT) and 351 (51.6%) for primary percutaneous coronary intervention (PPCI). TIMI 3-flow by TT was achieved for A, B and C RVI class in 65%, 64% and 0%, respectively and with PPCI in 93%, 91% and 87%, respectively.

RESULTS: For class A without RT, the mortality rate was 7.9%, with TT was reduced to 4.4% (P < 0.01) and with PPCI to 3.2% (P < 0.01). Considering TT vs PPCI, PPCI was superior (P < 0.05). For class B without RT the mortality was 27%, decreased to 13% with TT (P < 0.01) and to 8.3% with PPCI (P < 0.01). In a TT and PPCI comparison, PPCI was superior (P < 0.01). For class C without RT the in-hospital mortality was 80%, with TT was 100% and with PPCI, the rate decreased to 44% (P < 0.01). At 8 years, the mortality rate without RT for class A was 32%, for class B was 48% and for class C was 85%. When PPCI was successful, the long-term mortality was lower than previously reported for the 3 RVI classes (A: 21%, B: 38%, C: 70%; P < 0.001).

CONCLUSION: PPCI is superior to TT and reduces short/long-term mortality for all RVI categories. RVI CS patients should be encouraged to undergo PPCI at a specialized center.

Utility of cardiac magnetic resonance (CMR) in the evaluation of right ventricular (RV) involvement in patients with myocardial infarction (MI)

PURPOSE

The aim of this work was to compare the prevalence of right ventricle involvement in a population of patients with myocardial infarction as detected by cardiac magnetic resonance (CMR), clinical presentation, electrocardiographic (ECG) and echocardiographic criteria.

MATERIALS AND METHODS

A total of 97 consecutive patients, admitted to our institution for acute myocardial infarction, underwent a standard CMR examination within 5 days after the event. The presence of myocardial oedema and late enhancement of the right ventricle were compared to infarct location (anterior vs. inferior), clinical data, ECG, echocardiography results and other CMR findings. The results were analysed statistically using the Student's t test for independent samples and the K statistic.

RESULTS

Among the 97 patients included in the study, a diagnosis of right ventricular infarction was established in 12, 14 and 24 cases on the basis of the clinical data, the ECG and echocardiography, respectively. CMR demonstrated myocardial oedema and late enhancement of the right ventricle in 48 and 32 cases, respectively. The right ventricle was involved in 46 % of patients with inferior myocardial infarction (15/32) and in 30 % with anterior myocardial infarction (17/56), correlating to a worsening of both right and left ventricular performance (p = 0.001-0.05).

CONCLUSIONS

The right ventricle is frequently involved in myocardial infarction, correlating to a worse functional impairment of both ventricles and a worse prognosis. This finding, which is often underestimated by traditional cardiological tests, is well revealed by CMR, with potential clinical and therapeutic impact.

Right ventricular involvement in anterior myocardial infarction: a tissue Doppler-derived strain and strain rate study

OBJECTIVE

Strain and strain rate imaging is currently the most popular echocardiographic technique that reveals subclinical myocardial damage. There are currently no available data on this imaging method with regard to assessing right ventricular involvement in anterior myocardial infarction. Therefore, we aimed to evaluate right ventricular regional functions using a derived strain and strain rate imaging tissue Doppler method in patients who were successfully treated for their first anterior myocardial infarction.

METHODS

The patient group was composed of 44 patients who had experienced their first anterior myocardial infarction and had undergone successful percutaneous coronary intervention. Twenty patients were selected for the control group. The right ventricular myocardial samplings were performed in three regions: the basal, mid, and apical segments of the lateral wall. The individual myocardial velocity, strain, and strain rate values of each basal, mid, and apical segment were obtained.

RESULTS

The right ventricular myocardial velocities of the patient group were significantly decreased with respect to all three velocities in the control group. The strain and strain rate values of the right mid and apical ventricular segments in the patient group were significantly lower than those of the control group (excluding the right ventricular basal strain and strain rate). In addition, changes in the right ventricular mean strain and strain rate values were significant.

CONCLUSION

Right ventricular involvement following anterior myocardial infarction can be assessed using tissue Doppler based strain and strain rate.

Microvascular obstruction in the right ventricle in reperfused anterior myocardial infarction. Macroscopic and pathologic evidence in a swine model

INTRODUCTION

Data on right ventricular (RV) involvement in anterior myocardial infarction are scarce. The presence of RV microvascular obstruction (MVO) in this context has not been analyzed yet. The aim of the present study was to characterize the presence of MVO in the RV in a controlled experimental swine model of reperfused anterior myocardial infarction.

MATERIALS AND METHODS

Left anterior descending (LAD) artery-perfused area (thioflavin-S staining after selective infusion in LAD artery), infarct size (lack of triphenyltetrazolium-chloride staining) and MVO (lack of thioflavin-S staining in the core of the infarcted area) in the RV were studied. A quantitative (% of the ventricular volume) and semiquantitative (number of segments involved) analysis was carried out both in the RV and LV in a 90-min left anterior descending balloon occlusion and 3-day reperfusion model in swine (n=15).

RESULTS

RV infarction and RV MVO (>1 segment) were detected in 9 (60%) and 6 (40%) cases respectively. Mean LAD-perfused area, infarct size and MVO in the RV were 33.8 ± 13%, 13.53 ± 11.7% and 3.4 ± 4.5%. Haematoxylin and eosin stains and electron microscopy of the RV-MVO areas demonstrated generalized cardiomyocyte necrosis and inflammatory infiltration along with patched hemorrhagic areas. Ex-vivo nuclear magnetic resonance (T2 sequences) microimaging of RV-MVO showed, in comparison with remote non-infarcted territories, marked hypointense zones (corresponding to necrosis, inflammation and hemorrhage) in the core of hyperintense regions (corresponding to edema).

CONCLUSIONS

In reperfused anterior myocardial infarction, MVO is frequently present in the RV. It is associated with severe histologic repercussion on the RV wall. Nuclear magnetic resonance appears as a promising technique for the noninvasive detection of this phenomenon. Further studies are warranted to evaluate the pathophysiological and clinical implications.

Assessing myocardial recovery following ST-segment elevation myocardial infarction: short- and long-term perspectives using cardiovascular magnetic resonance

Myocardial recovery after revascularization for ST-segment elevation myocardial infarction (STEMI) remains a significant diagnostic and, despite novel treatment strategies, a therapeutic challenge. Cardiovascular magnetic resonance (CMR) has emerged as a valuable clinical and research tool after acute STEMI. It represents the gold standard for functional and morphological evaluation of the left ventricle. Gadolinium-based perfusion and late-enhancement viability imaging has expanded our knowledge about the underlying pathologies of inadequate myocardial recovery. T2-weighted imaging of myocardial salvage after early reperfusion of the infarct-related artery underlines the effectiveness of current invasive treatment for STEMI. In the last decade, the number of publications on CMR after acute STEMI continued to rise, with no plateau in sight. Currently, CMR research is gathering robust prognostic data on standardized CMR protocols with the aim to substantially improve patient care and prognosis. Beyond established CMR protocols, more specific methods such as magnetic resonance relaxometry, myocardial tagging, 4D phase-contrast imaging and novel superparamagnetic contrast agents are emerging. This review will discuss the currently available data on the use of CMR after acute STEMI and take a brief look at developing new methods currently under investigation.

Cardiac MRI of acute coronary syndrome

Acute coronary syndrome (ACS) is a major cause of morbidity and mortality worldwide. New serological biomarkers, such as troponins, have improved the diagnosis of ACS; however, the diagnosis of ACS can still be difficult as there is marked heterogeneity in its presentation and significant overlap with other disorders presenting with chest pain. Evidence is accumulating that cardiac MRI provides information that can aid the detection and differential diagnosis of ACS, guide clinical decision-making and improve risk-stratification after an event. In this review, we present the relevant cardiac MRI techniques that can be used to detect ACS accurately, provide differential diagnosis, identify the sequelae of ACS, and determine prognostication after ACS.

Three-dimensional transesophageal echocardiography for perioperative right ventricular assessment

BACKGROUND

In high-risk cardiac procedures, dynamic analysis of right ventricular (RV) performance is desirable, but the geometric complexity of the RV limits the applicability of current two-dimensional echocardiographic imaging techniques. This study aimed to evaluate the utility of three-dimensional transesophageal echocardiography (TEE) for the perioperative assessment of RV function and dimensions.

METHODS

Patients undergoing cardiac surgical procedures with complete TEE examinations were identified and reviewed according to current guidelines to exclude patients with significant coexisting valvular regurgitation. Full-volume, three-dimensional datasets were analyzed by two independent investigators using stand-alone software, and left ventricular and RV dimensions were recorded.

RESULTS

Datasets from 50 patients undergoing cardiac surgical procedures were evaluated for this study. The mean RV volume was 111.7 mL (range, 37.5 to 349.7 mL) at end diastole and 67.6 mL (range, 25.5 to 274.4 mL) at end systole. Intraobserver reliability was 0.93 and 0.90 for end diastolic and 0.77 and 0.87 for end systolic volumes. The interobserver reliability for RV volumes was 0.83 at end diastole and 0.86 at end systole. The mean stroke volume was 43.6 mL (range, 12 to 111.2 mL) for the RV and 49.1 mL (range, 19.9 to 102.8 mL) for the left ventricle; the correlation coefficient between the two was 0.85.

CONCLUSIONS

Three-dimensional TEE volumetric measurements were reproducible across a wide range of RV dimensions. As postulated by the continuity principle, stroke volume measurements between both ventricles correlated well, supporting the validity of this approach. Therefore, our work provides preliminary evidence that three-dimensional TEE offers reproducible information about RV function and size in the dynamic and complex perioperative setting of cardiac surgical procedures.

The role of cardiac magnetic resonance in the evaluation of patients presenting with suspected or confirmed acute coronary syndrome

Cardiac magnetic resonance imaging (CMR) has an important emerging role in the evaluation and management of patients who present with symptoms concerning for acute coronary syndrome (ACS). This paper discusses the role of CMR in the emergency department setting, where CMR can aid in the early and accurate diagnosis of non-ST elevation ACS in low and intermediate risk patients. For those with confirmed myocardial infarction (MI), CMR provides comprehensive prognostic information and can readily diagnose structural complications related to MI. Furthermore, the pattern of late gadolinium enhancement (LGE) seen on CMR can help determine the etiology of cardiac injury in the subset of patients presenting with ACS who do not have obstructive coronary artery disease by angiography.