Right ventricular myocardial infarction: pathophysiology, diagnosis, and management

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.

Long-term outcomes from upgrade to cardiac resynchronisation therapy in ischaemic versus non-ischaemic heart disease

BACKGROUND

Cardiac resynchronisation therapy (CRT) can be necessary in patients with chronic heart failure, who have already been provided with transvenous cardiac implantable electrical devices. Upgrade procedures revealed controversial results, while long-term outcomes regarding underlying Ischaemic- (ICM) or Non-Ischaemic heart disease (NICM) have yet to be described.

METHODS

The Mannheim Cardiac Resynchronisation Therapy Registry (MARACANA) was designed as a retrospective observational single-centre registry, including all CRT implantations from 2013-2021 (n = 459). CRT upgrades (n = 136) were retrospectively grouped to either ICM (n = 84) or NICM (n = 52) and compared for New York Heart Association classification (NYHA), paced QRS-width, left ventricular ejection fraction (LVEF), tricuspid annular plane systolic excursion (TAPSE) and other heart failure modification aspects in the long-term (59.3 ± 5 months).

RESULTS

Baseline-characteristics including paced QRS-width, upgrade indications or NYHA-classification were comparable for both groups (group comparison p>.05). The CRT upgrade improved NYHA (ICM: 2.98 ± 0.4 to 2.29 ± 0.7, NICM: 2.94 ± 0.5 to 2.08 ± 0.5) and the LVEF (ICM: 27.2 ± 6.6 to 38.25 ± 8.8, NICM: 30.2 ± 9.4 to 38.7 ± 13.8%) after five years, irrespective of underlying heart disease (each group p < .05, group comparison p>.05). Only ICM revealed significant improvements in TAPSE (15.9 ± 4.1 to 18.9 ± 4.1 mm) and narrowing of the paced QRS-width (185.4 ± 29 to 147.2 ± 16.3 ms) after five years (each p < .05).

CONCLUSIONS

Upgrade to CRT might improve heart failure symptoms and left-ventricular systolic function in the long-term, irrespective of underlying ischaemic or non-ischaemic heart disease.

Assessment of Right Ventricular Function by Strain Imaging in Patients Presenting with Acute Myocardial Infarction: An Original Research

Objective

This study sought to determine the relationship between right ventricular (RV) function and clinical variables and prognosis in individuals with acute myocardial infarction (AMI) utilizing strain imaging.

Materials and Methods

A prospective observational research involving 150 patients who had been admitted with AMI was carried out. Utilizing two-dimensional speckle-tracking strain imaging, RV function was assessed. Age, sex, risk factors, and comorbidities were recorded as clinical parameters. A 12-month follow-up was conducted to assess major adverse cardiovascular events (MACE).

Results

65% of the study's participants were men, with a mean age of 58.2 years. When compared to a healthy control group, individuals with AMI had significantly lower RV longitudinal strain (RVLS) (P 0.001). RVLS and left ventricular ejection fraction had a statistically significant connection (r = 0.642, P 0.001). Patients with compromised RVLS had a greater rate of MACE over the follow-up period compared to those with maintained RV function (P = 0.014).

Conclusion

In conclusion, strain imaging offers useful information for evaluating RV function in patients with AMI. Reduced left ventricular performance and a higher likelihood of unfavorable clinical outcomes are linked to impaired RVLS. Utilizing strain imaging to detect RV dysfunction early can help direct treatment plans and enhance patient outcomes.

Intravenous Diuresis in Severe Precapillary Pulmonary-Hypertension-Related Right Heart Failure: Effects on Renal Function and Blood Pressure

In patients with right heart failure (RHF) and pulmonary hypertension (PH), classical teaching often advises cautious diuresis in the setting of 'preload dependence' to avoid renal injury and hemodynamic compromise. However, while this physiology may hold true in some clinical settings, such as acute ischemia with right ventricular infarction, it cannot necessarily be extended to PH-related RHF. Rather, in patients with precapillary PH and decompensated RHF, diuresis aimed to decongest the right heart and systemic venous system may be directly beneficial. This study aimed to evaluate the effects of diuresis on renal function and blood pressure in patients with severe precapillary PH. A retrospective chart review was conducted on 62 patients with severe precapillary PH admitted for decompensated RHF. The hemodynamic phenotype of these patients was characterized by invasive hemodynamics and echocardiographic data. Laboratory and hemodynamic data were collected at both admission and discharge. After large-volume diuresis in this patient population, there was an improvement in both glomerular filtration rate and creatinine. While there was a decline in blood pressure after diuresis, this was not clinically significant, given the blood pressure remained in a normal range with improvement in renal function. In conclusion, this study demonstrated that despite concern for preload dependence, significant diuresis in patients with acute decompensated RHF from precapillary PH is not only safe but beneficial.

Right Ventricular Global Longitudinal Strain and Short-Term Prognosis in Patients With First Acute Myocardial Infarction

Right ventricular (RV) dysfunction after acute myocardial infarction (AMI) is a recognized predictor of dismal prognosis. However, the most reliable RV index to predict mortality early after revascularization remains undetermined. This study aimed to explore the ability of RV global longitudinal strain (GLS) to predict inhospital mortality in patients with first AMI. All consecutive patients with first AMI were prospectively enrolled from March 2022 until February 2023. An echocardiogram was performed 24 hours after successful revascularization and RV GLS alongside conventional echocardiographic indexes were measured. Inhospital mortality was recorded. A total of 300 patients (age 61.2 ± 11.8 years, 74% male) were included in the study. RV GLS was the only RV performance index that differed significantly between anterior and inferior ST-segment-elevation patients with AMI (14.5 ± 5.2% vs 17.4 ± 5.1% respectively, p <0.001). After revascularization, 23 patients (7.7%) died in hospital. The model of Global Registry of Acute Coronary Event risk score and left ventricular ejection fraction, built for predicting inhospital mortality, significantly improved its prognostic performance only by the addition of RV GLS (chi-square value increase by 7.485, p = 0.006) compared with the other RV function indexes. RV GLS was independently associated with inhospital mortality (odds ratio 0.83, 95% confidence interval 0.71 to 0.97, p = 0.017) after adjustment for Global Registry of Acute Coronary Event risk score and left ventricular ejection fraction. Echocardiographic RV GLS measured 24 hours after revascularization in patients with first AMI outperformed conventional RV function indexes in predicting inhospital mortality.

Haemodynamic effects of inhaled nitric oxide in acute myocardial infarction complicated by right heart failure under ECPELLA support: case report

Background

Recently, mechanical support obtained with the combination of venoarterial extracorporeal membrane oxygenation (VA-ECMO) and an Impella device, together referred to as ECPELLA, has been shown to be effective for acute myocardial infarction with cardiogenic shock. However, methods for withdrawing VA-ECMO in acute myocardial infarction cases complicated by right ventricular dysfunction are yet to be established. Here, we report the effective use of inhaled nitric oxide during the weaning of VA-ECMO from the ECPELLA management of a patient with acute myocardial infarction with cardiogenic shock.

Case summary

An 81-year-old man with an acute extensive anterior wall myocardial infarction with cardiogenic shock was supported with ECPELLA to improve his haemodynamics. During ECPELLA, the Impella device could not maintain sufficient flow. Echocardiography revealed a small left ventricle and an enlarged right ventricle, indicating acute right heart failure. Inhaled nitric oxide was initiated to reduce right ventricle afterload, which decreased pulmonary artery pressure from 34/20 to 27/13 mmHg, improved right and left ventricle sizes, and stabilized the Impella support. Afterward, VA-ECMO could be withdrawn because the Impella alone was sufficient for haemodynamic support.

Discussion

Inhaled nitric oxide improved right ventricle performance in a patient with severe myocardial infarction with right heart failure supported by ECPELLA. Thus, we suggest that inhaled nitric oxide facilitates the weaning of VA-ECMO from patients with refractory right ventricular dysfunction who are supported by ECPELLA.

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.

Assessment of Right Ventricular Function-a State of the Art

PURPOSE OF REVIEW

The right ventricle (RV) has a complex geometry and physiology which is distinct from the left. RV dysfunction and failure can be the aftermath of volume- and/or pressure-loading conditions, as well as myocardial and pericardial diseases.

RECENT FINDINGS

Echocardiography, magnetic resonance imaging and right heart catheterisation can assess RV function by using several qualitative and quantitative parameters. In pulmonary hypertension (PH) in particular, RV function can be impaired and is related to survival. An accurate assessment of RV function is crucial for the early diagnosis and management of these patients. This review focuses on the different modalities and indices used for the evaluation of RV function with an emphasis on PH.

Management of Acute Right Ventricular Failure

PURPOSE OF REVIEW

Acute right ventricular failure (RVF) is a frequent condition associated with high morbidity and mortality. This review aims to provide a current overview of the pathophysiology, presentation, and comprehensive management of acute RVF.

RECENT FINDINGS

Acute RVF is a common disease with a pathophysiology that is not completely understood. There is renewed interest in the right ventricle (RV). Some advances have been principally made in chronic right ventricular failure (e.g., pulmonary hypertension). Due to a lack of precise definition and diagnostic tools, acute RVF is poorly studied. Few advances have been made in this field. Acute RVF is a complex, frequent, and life-threatening condition with several etiologies. Transthoracic echocardiography (TTE) is the key diagnostic tool in search of the etiology. Management includes transfer to an expert center and admission to the intensive care unit (ICU) in most severe cases, etiological treatment, and general measures for RVF.

Prognostic value of right ventricular diastolic dysfunction in patients with inferior ST-elevated myocardial infarction

BACKGROUND

Right ventricle infarction (RVI) is predominantly a complication of inferior wall myocardial infarction; it occurs in approximately one third of these patients. Right ventricular dysfunction in patients with inferior STEMI and RV infarction was under assessed. Nevertheless, studies which targeted RV assessment by echocardiography, did not routinely evaluate RV diastolic dysfunction. In this study, we aimed to evaluate RV diastolic dysfunction and its prognostic value in patients with inferior STEMI and RVI.

RESULTS

Sixty patients with inferior STEMI and RV infarction, who underwent primary PCI were enrolled in the study. Patients with pre-existing clinical conditions that might affect RV function, were excluded. Echocardiography was performed within twenty-four hours following the PCI, to assess the RV systolic and diastolic functions with special focus on tricuspid inflow velocities (E velocity, A velocity and E/A ratio) by pulsed wave (PW) doppler and tricuspid annular velocities by tissue doppler index (TDI) (E', A' and E/E' ratio). Clinical features and MACE, including cardiogenic shock, arrhythmia, stroke, reinfarction and death were analyzed in all our patients within 3 months follow up period. The average age of the study population was 51.58 ± 10.11 years, 10% were females. Five patients developed MACE (death, cardiogenic shock and pulmonary edema, anterior STEMI and cardiogenic shock, recurrent inferior STEMI, and arrhythmia and stroke), of whom four occurred in hospital within the first 48 h. Patients who developed MACE had high filling pressures, as all of them had E/E' > 6. E' velocity ≤ 6 cm/sec was associated with increased MACE as 25% of patients with E' velocity ≤ 6 had MACE compared with 2.3% of patients with E' velocity > 6 with a p value of 0.015.

CONCLUSIONS

Tricuspid annular velocities by TDI are essential when evaluating RV diastolic dysfunction. E/E' and E' velocity have a prognostic value in patients with inferior STEMI and RV infarction; E/E' > 6 and E' velocity ≤ 6 cm/sec were associated more MACE in patients with inferior STEMI and RVI.

Clinical characteristics and prognosis differences between isolated right and left ventricular myocardial infarction in the Chinese population: a retrospective study

Background and aims

Acute myocardial infarction (AMI) is divided into left ventricular myocardial infarction (LVMI) and right ventricular myocardial infarction (RVMI) according to the regions of myocardial ischemic necrosis. Clinical characteristics, treatment strategies, and prognosis differences between isolated RVMI and LVMI have not been well characterized. This study aimed to explore this difference of patients with isolated RVMI and LVMI.

Methods

This retrospective cohort study included 3,506 patients hospitalized with coronary angiography diagnosed type 1 myocardial infarction (MI). Characteristics of admission and treatment strategies were compared in patients with isolated RVMI and LVMI. COX proportional hazards models with and without inverse probability of treatment weighting (IPTW) adjustment were performed to estimate the difference in all-cause and cardiovascular mortality between the two groups.

Results

In this retrospective study, we found the frequency of isolated RVMI was significantly lower in the population than that of isolated LVMI (406 (11.6%) vs 3,100 (88.4%)). Patients with isolated RVMI have similar age, sex, and comorbidities to the patients with isolated LVMI. However, patients with isolated RVMI have lower heart rate and blood pressure, but higher rates of cardiogenic shock and atrioventricular block. It is noteworthy that patients with isolated RVMI are more likely to be complicated with the multivessel lesion. Patients with isolated RVMI have lower risk of all-cause mortality (HR 0.36; 95% CI [0.24-0.54], p < 0.001) and cardiovascular mortality (HR 0.37; 95% CI [0.22-0.62], p < 0.001) than patients with isolated LVMI.

Conclusions

This study showed that patients with isolated RVMI and LVMI have similar baseline characteristics. However, the clinical manifestations were different in the isolated RVMI and LVMI patients. This study revealed a better prognosis of isolated RVMI patients compared to isolated LVMI, which indicates the ischemic region could be considered in AMI risk stratification models for better assessment of risk for adverse clinical events.

Nondominant Right Coronary Artery Occlusion: Small Vessel, Dramatic Sequelae

Nondominant right coronary artery (NDRCA) occlusion is rare and generally affects a small volume of myocardium. Despite this, NDRCA occlusion can result in dramatic clinical sequelae. These cases demonstrate the characteristic electrocardiographic findings and consequences of NDRCA occlusion, highlighting the importance of recognition of this pathologic condition to institute appropriate management. (Level of Difficulty: Intermediate.).

Long-term outcomes in inferior ST-segment elevation myocardial infarction patients with right ventricular myocardial infarction

OBJECTIVE

To evaluate the prognostic influence of the presence of right ventricular myocardial infarction (RVMI) on patients with inferior ST-segment elevation myocardial infarction (STEMI) in the contemporary reperfusion era.

METHODS

9308 patients with inferior STEMI were included from the prospective, nationwide, multicenter China Acute Myocardial Infarction Registry, including 1745 (18.75%) patients with RVMI and 7563 (81.25%) patients without RVMI. The primary outcome was two-year all-cause mortality. The secondary outcome was major adverse cardiac and cerebrovascular event (MACCE) defined as a composite of all-cause mortality, recurrent MI, revascularization, stroke, and major bleeding.

RESULTS

After two-year follow up, there were no significant differences between inferior STEMI patients with or without RVMI in all-cause mortality (12.0% vs 11.3%; adjusted HR: 1.05; 95% CI: 0.90 to 1.24; P = 0.5103). Inferior STEMI with RVMI was associated with higher risk of MACCE (25.6% vs 22.0%; adjusted HR: 1.17; 95% CI: 1.05 to 1.31; P = 0.0038), revascularization (10.3% vs 8.1%; adjusted HR: 1.23; 95% CI: 1.03 to 1.48; P = 0.0218), and major bleeding (4.6% vs 2.7%; adjusted HR: 1.56; 95% CI: 1.18 to 2.07; P = 0.0019). Primary percutaneous coronary intervention (PCI) and thrombolysis were independent predictors to decrease all-cause mortality. For patients who received timely reperfusion, RVMI involvement did not increase all-cause mortality, whereas for those who did not undergo reperfusion, RVMI increased all-cause mortality (20.3% vs 15.7%; HR: 1.34; 95% CI: 1.10 to 1.63).

CONCLUSION

RVMI did not increase all-cause mortality for inferior STEMI patients in contemporary reperfusion era, whereas the risk was increased for patients with no reperfusion treatment.

Perioperative Right Ventricular Dysfunction: Analysis of Outcomes

Right ventricular dysfunction (RVD) is a well-known prognostic factor for adverse outcomes in cardiovascular medicine. The right ventricle (RV) in medically managed heart failure patients and in surgical patients perioperatively generally is overshadowed by left ventricular disease. However, with advancement of various diagnostic tools and better understanding of its functional anatomy, the role of the RV is emerging in many clinical conditions. The failure of one ventricle has significant effect on the function of the other ventricle and it is predominantly due to ventricular interdependence.¹ The etiology of RVD is multifactorial and irrespective of etiology. RVD has been associated with significant increases in morbidity and mortality in various clinical scenarios.^2,3 The primary objective of this comprehensive review is to analyze various etiology-related outcomes of RVD in the perioperative population.

Evaluation of right ventricular dyssynchrony in patients with acute inferior myocardial infarction and its relation with mortality

PURPOSE

The aim of this study was to evaluate right ventricle (RV) dyssynchrony and its relation with mortality using speckle-tracking echocardiography (STE) in patients with acute inferior myocardial infarction (IMI).

METHODS

One hundred and fifty-eight consecutive patients with acute IMI treated with primary percutaneous coronary intervention, and 44 healthy subjects were included. RV myocardial involvement (RVMI) was defined as an elevation >1 mm in V1 or V4R and/or the presence of a culprit lesion at the proximal portion of the first RV marginal branch after reviewing coronary angiography. Patients were followed for 3 years to determine the cardiovascular mortality.

RESULTS

Overall, 70 patients with IMI had RVMI. IMI patients had significantly higher RV peak systolic longitudinal strain dyssynchrony (PLSSD) index, lower peak longitudinal systolic strain (PLSS), longer time to PLSS, and time to PLSS differences compared to healthy controls while the patients with RVMI had significantly worse values compared to patients without RVMI and healthy controls. Twenty-seven patients (17.1%) died within 2 years. RVMI was more prevalent in mortality group, and they had significantly higher RV PSSD index, whereas they had lower RV free wall PLSS and longer time to PLSS differences. Receiver operating characteristics (ROC) analysis revealed that a RV PLSSD index > 65 ms predicted mortality with a sensitivity of 88.9% and specificity of 71.8% in IMI patients.

CONCLUSIONS

Intra- and inter-ventricular dyssynhcrony may develop in patients with acute IMI, especially in those with RV involvement, which might have a negative effect on the prognosis of these patients.

Impella RP support in refractory right ventricular failure complicating acute myocardial infarction with unsuccessful right coronary artery revascularization

BACKGROUND

Impella RP has been used to treat right ventricular failure (RVF) developing in various clinical settings that underlay different pathological mechanisms and lead to distinct prognostic implications.

METHODS

This is a single-centre retrospective study including all consecutive patients, from January 2015 to December 2018, with inferior STEMI due to acute thrombotic occlusion of right coronary artery (RCA) and unsuccessful primary percutaneous coronary intervention (PCI) complicated by refractory RVF managed with an Impella RP device.

RESULTS

A total of 5 patients have been treated. The mean age was 73 ± 9 years, 80% were males. All patients, except one, were hemodynamically stable at hospital admission. In all patients, PCI resulted unsuccessful (final TIMI flow < 3), with subsequent development of refractory RVF and cardiogenic shock in the catheterization laboratory, despite the use of inotropes and intra-aortic balloon pump (IABP). In 80% of the cases, Impella RP was placed immediately after PCI. Hemodynamics improved immediately after initiation of Impella RP support, with an increase in systolic blood pressure from 91 ± 17 to 136 ± 13 mmHg, a decrease in central venous pressure from 16 ± 2.5 to 12 ± 4 mmHg and a resolution in lactates from 4.5 ± 2.5 to 1.6 ± 0.7 mg/dL. Mean duration of IABP and Impella RP support were 4 and 7 days, respectively. RV recovery occurred in 80% of the cases. All patients survived at 30-day.

CONCLUSIONS

In patients with AMI complicated by unsuccessful revascularization of RCA and refractory RVF, the use of Impella RP device resulted in immediate hemodynamic benefit with reversal of shock and favourable survival at 30-day.

A patient with simultaneous anterior and inferior ST-segment elevation after percutaneous coronary intervention

A patient who presented with acute inferior-right ventricular (RV) ST-segment elevation (STE) myocardial infarction (MI) is described. Coronary angiography showed a mid-right coronary artery (RCA) occlusion and high-grade proximal left anterior descending (LAD) artery stenoses. Electrocardiography (ECG) after stent angioplasty to the RCA showed new STE in leads V1-V6. Whereas STE pattern recognition was misleading, ECG analysis using vector concepts enabled exclusion of anterior MI due to proximal LAD artery occlusion and recognition of the RV origin of this ECG picture. The ability of the ECG to "capture" RV dilation that enabled the manifestation of this ECG picture is highlighted.

Evaluation and Management of Right-Sided Heart Failure: A Scientific Statement From the American Heart Association

Background and Purpose:

The diverse causes of right-sided heart failure (RHF) include, among others, primary cardiomyopathies with right ventricular (RV) involvement, RV ischemia and infarction, volume loading caused by cardiac lesions associated with congenital heart disease and valvular pathologies, and pressure loading resulting from pulmonic stenosis or pulmonary hypertension from a variety of causes, including left-sided heart disease. Progressive RV dysfunction in these disease states is associated with increased morbidity and mortality. The purpose of this scientific statement is to provide guidance on the assessment and management of RHF.

Methods:

The writing group used systematic literature reviews, published translational and clinical studies, clinical practice guidelines, and expert opinion/statements to summarize existing evidence and to identify areas of inadequacy requiring future research. The panel reviewed the most relevant adult medical literature excluding routine laboratory tests using MEDLINE, EMBASE, and Web of Science through September 2017. The document is organized and classified according to the American Heart Association to provide specific suggestions, considerations, or reference to contemporary clinical practice recommendations.

Results:

Chronic RHF is associated with decreased exercise tolerance, poor functional capacity, decreased cardiac output and progressive end-organ damage (caused by a combination of end-organ venous congestion and underperfusion), and cachexia resulting from poor absorption of nutrients, as well as a systemic proinflammatory state. It is the principal cause of death in patients with pulmonary arterial hypertension. Similarly, acute RHF is associated with hemodynamic instability and is the primary cause of death in patients presenting with massive pulmonary embolism, RV myocardial infarction, and postcardiotomy shock associated with cardiac surgery. Functional assessment of the right side of the heart can be hindered by its complex geometry. Multiple hemodynamic and biochemical markers are associated with worsening RHF and can serve to guide clinical assessment and therapeutic decision making. Pharmacological and mechanical interventions targeting isolated acute and chronic RHF have not been well investigated. Specific therapies promoting stabilization and recovery of RV function are lacking.

Conclusions:

RHF is a complex syndrome including diverse causes, pathways, and pathological processes. In this scientific statement, we review the causes and epidemiology of RV dysfunction and the pathophysiology of acute and chronic RHF and provide guidance for the management of the associated conditions leading to and caused by RHF.

Impact of right ventricular diastolic dysfunction on clinical outcomes in inferior STEMI

BACKGROUND

The aim of this study was to investigate the prognostic value of restrictive right ventricular filling pattern (RRVFP) in patients with the first acute inferior wall myocardial infarction (IWMI) complicated by right ventricular myocardial infarction (RVMI) undergoing primary percutaneous coronary intervention (p-PCI).

METHOD

A total of 152 patients with acute IWMI complicated by RVMI undergoing p‑PCI were divided into two groups according to the presence of RRVFP. RRVFP was defined as tricuspid diastolic early/late flow velocities (Et/At) > 2 and Et deceleration time (DT) < 120 ms.

RESULTS

There were 23 patients with RRVFP in the study cohort. At, DTt, isovolumetric relaxation time (IVRT), and tissue Doppler tricuspid annular late velocity (A't) were reduced significantly in patients with RRVFP than in those without RRVFP (At 19.6 ± 2.7 vs. 39.1 ± 7.4 cm/s, p < 0.001; DTt 106 ± 13 vs.156 ± 21 ms, p = 0.001; IVRT 59 ± 6.7 vs. 62 ± 7.4 ms, p = 0.01; A't 4.6 ± 1.1 vs. 8.6 ± 1.05, p = 0.001). Et/At ratios were higher in patients with RRVFP than in those without RRVFP (Et/At 2.20 ± 0.2 vs. 1.15 ± 0.37, p < 0.001). Et, tissue Doppler tricuspid annular early velocity (E't), E't/A't ratio, and Et/E't ratio were not significantly different between groups (Et 43.3 ± 5.4 vs. 40.7 ± 9.2 cm/s p = 0.18; E't 8.8 ± 1.4 vs. 9.5 ± 2.3, p = 0.15; E't/A't 1.08 ± 0.24 vs. 1.13 ± 0.30, p = 0.52; Et/E't ratio 5.0 ± 1.1 vs. 4.5 ± 1.5 p = 0.09). Presence of E't/A't > 2, short DTt, RRVFP, unsuccessful p‑PCI, and cardiogenic shock on admission were independent predictors of in-hospital mortality (p < 0.05) in multivariable logistic regression analysis.

CONCLUSION

Presence of RRVFP is associated with in-hospital mortality in patients presenting with their first IWMI complicated by RVMI.

Sevoflurane anesthesia during acute right ventricular ischemia in pigs preserves cardiac function better than propofol anesthesia

BACKGROUND

The intention of the present study was to evaluate possible cardioprotective properties of inhalation anesthesia with sevoflurane.

METHODS AND MATERIALS

A porcine, open-chest model of right ventricular ischemia was used in 7 pigs receiving inhalation anesthesia with sevoflurane. The model was earlier developed and published by our group, using pigs receiving intravenous anesthesia with propofol. They served as controls. The animals were observed for three hours after the induction of right ventricular ischemia by ligation of the main branches supplying the right ventricular free wall.

RESULTS

In the sevoflurane group, the cardiac output recovered 2 hours after the induction of ischemia and intact right ventricular stroke work was observed. In the propofol group, no such recovery occurred. The release of troponin T was significantly lower than in the sevoflurane group.

CONCLUSIONS

Inhalation anesthesia with sevoflurane seems superior to intravenous anesthesia with propofol in acute right ventricular ischemic dysfunction.

Assessment of left and right ventricular diastolic and systolic functions using two-dimensional speckle-tracking echocardiography in patients with coronary slow-flow phenomenon

OBJECTIVE

Coronary slow-flow phenomenon (CSFP) is an angiographic diagnosis characterised by a low rate of flow of contrast agent in the normal or near-normal epicardial coronary arteries. Many of the patients with CSFP may experience recurrent acute coronary syndromes. However, current clinical practice tends to underestimate the impact of CSFP due to the yet unknown effect on the cardiac function. This study was performed to evaluate left ventricular (LV) and right ventricular (RV) diastolic and systolic functions, using two-dimensional (2D) longitudinal strain and strain rate, in patients with CSFP, and to determine the relationships between the thrombolysis in myocardial infarction (TIMI) frame count (TFC) and LV and RV diastolic and systolic functions.

METHODS

Sixty-three patients with CSFP and 45 age- and sex-matched controls without CSFP were enrolled in the study. Diagnosis of CSFP was made by TFC. LV and RV diastolic and systolic functions were assessed by 2D speckle-tracking echocardiography.

RESULTS

LV peak early diastolic longitudinal strain rate (LSRe) was lower in patients with CSFP than in controls (P = 0.01). LV peak systolic longitudinal strain (LS) and LV peak systolic longitudinal strain rate (LSRs) were lower in patients with CSFP than in controls (P = 0.004 and P = 0.03, respectively). There was no difference in LV ejection fraction. RV peak early diastolic longitudinal strain rate (RSRe) was lower in patients with CSFP than in controls (P = 0.03). There were no differences in RV peak systolic longitudinal strain (RS), RV peak systolic longitudinal strain rate (RSRs), or RV fractional area change among the groups. The mean TFC correlated negatively with LSRe and RSRe in patients with CSFP (r = -0.26, P = 0.04 and r = -0.32, P = 0.01, respectively).

CONCLUSIONS

LV diastolic and systolic functions were impaired in patients with CSFP. CSFP also affected RV diastolic function, but not RV systolic function.

Impaired RV global longitudinal strain is associated with poor long-term clinical outcomes in patients with acute inferior STEMI

OBJECTIVES

The aim of this study was to assess the long-term prognostic value of the global longitudinal strain of the right ventricle (GLSRV) in patients with inferior ST-segment elevation myocardial infarction (STEMI) who underwent primary percutaneous coronary intervention (PCI).

BACKGROUND

RV systolic dysfunction is an important prognostic factor in patients with inferior STEMI.

METHODS

All consecutive inferior STEMI patients were included from January 2005 to December 2013. RV systolic function was analyzed with GLSRV using velocity vector imaging (Siemens, Mountain View, California), as well as conventional echocardiographic indices, including right ventricular fractional area change (RVFAC) and tricuspid annular plane systolic excursion (TAPSE).

RESULTS

We analyzed a total of 282 consecutive inferior STEMI patients (212 men, age 63 ± 13 years) treated with primary PCI. During the follow-up period (54 ± 35 months), 59 patients (21%) had 1 or more major adverse cardiovascular event (MACE) (43 deaths, 7 nonfatal MI, 4 target vessel revascularization, and 6 heart failure admission). The best cutoff value of GLSRV for the prediction of MACE was ≥-15.5% (area under the curve = 0.742, p < 0.001) with a sensitivity of 73% and a specificity of 65%. GLSRV showed better sensitivity and specificity than RVFAC and TAPSE. After multivariate analysis, GLSRV showed a higher c-statistic value (0.770) than RVFAC (0.749) and TAPSE (0.751) in addition to age, Killip class, troponin-I, left ventricular (LV) ejection fraction and RV infarction. Patients with GLSRV≥-15.5% showed significantly lower 5-year survival rate (74 ± 5% vs. 89 ± 3%, p < 0.001) and lower MACE-free survival rate (64 ± 5% vs. 87 ± 3%, p < 0.001) than the control group.

CONCLUSIONS

Because GLSRV showed additive predictive value to age and LV function, it can be the strongest parameter of RV systolic function evaluating the prognosis after PCI for acute inferior STEMI particularly in patients with preserved LV function.

A porcine model for acute ischaemic right ventricular dysfunction

OBJECTIVES

To establish an experimental model for acute ischaemic isolated right ventricular dysfunction and the subsequent haemodynamic changes.

METHODS

An open-chest porcine model with ischaemic dysfunction of the right ventricle induced by ligation of the three main branches supporting the right ventricular free wall. Invasive monitoring of mean arterial blood pressure (MAP), central venous pressure (CVP), left atrial pressure (LAP) and right ventricular pressure (RVP); ultrasonic measurement of cardiac output (CO) and calculation of haemodynamic parameters such as stroke volume (SV), systemic vascular resistance (SVR), pulmonary vascular resistance (PVR) and right ventricular stroke work (RVSW) using standard formulae.

RESULTS

The ischaemic challenge to the right ventricle resulted in a significant (≥30%) reduction in RVSW associated with an increase (6-25%) in CVP and reduction (8-18%) in pulmonary artery pressure (PAP) despite unchanged PVR, all reflecting the failing right ventricle. There was also a significant drop in CO (14-22%) despite unchanged LAP indicating lessened transpulmonary delivery of left ventricular preload due to the failing right ventricle causing the haemodynamic compromise rather than left ventricular failure. Supraventricular and ventricular arrhythmias occurred in three and two out of seven pigs, respectively-all of which except one were successfully resuscitated with cardioversion and/or defibrillation.

CONCLUSIONS

This novel open-chest porcine model of induced ischaemia of the right ventricular free wall resulted in significant haemodynamic compromise confirmed using standard haemodynamic measurements making it useful for further research on acute, ischaemic isolated right ventricular failure.

IL-6 and its receptors in coronary artery disease and acute myocardial infarction

Biomarkers such as interleukin-6 (IL-6), soluble interleukin-6 receptor (sIL-6R), and high sensitive C-reactive protein (hsCRP) have been reported to be elevated in acute myocardial infarction (AMI). The aim of this study is to determine the relationship between these markers during AMI, as well as their relationship to clinical parameters in an effort to discern their predictive potential in cardiac events. Serum was collected from 73 patients with; AMI, stable coronary artery disease (CAD), and controls during cardiac catheterization. Biomarker levels were determined and correlated with clinical data. IL-6 (11.75pg/ml, P<0.05) and sIL-6R (41,340pg/ml, P=0.05) were elevated in AMI compared with CAD and controls. At presentation, hsCRP was elevated in AMI patients (4.69mg/L) compared to controls (2.69mg/L, P<0.05); however, there was a significant decrease in hsCRP between AMI (4.69mg/L) and CAD patients (7.4mg/L, P<0.05). After 24h post-AMI hsCRP levels were increased compared to stable CAD (60.46mg/L, P<0.05) and were preceded by increased IL-6 at presentation. Soluble Gp130 (sGp130) showed no significant change between AMI, CAD, and control patients. However, sGp130 positively correlated with peak troponin in AMI (R=0.587, P<0.01), and negatively correlated with previous AMI (R=-0.382, P<0.05). Circulating monocyte mRNA expression isolated from selected AMI patients showed an increase in IL-6 mRNA (5.28-fold, P<0.01) and a decrease in both IL-6R (0.374-fold, P<0.01) and sGp130 mRNA (0.38-fold, P<0.01) as compared to CAD and controls. Results demonstrate that IL-6 and sIL-6R are associated with AMI and cardiac injury. These data support the hypothesis that trans-IL-6 receptor binding may alter intracellular signaling, and blocking of IL-6 receptor binding may be pathogenic in AMI. These data may be predictive of mechanism(s) by which plaques become unstable and rupture.

Imaging the right heart: the use of integrated multimodality imaging

During recent years, right ventricular (RV) structure and function have been found to be an important determinant of outcome in different cardiovascular and also pulmonary diseases. Currently, echocardiography and cardiac magnetic resonance (CMR) imaging are the two imaging modalities most commonly used to visualize the RV. Most structural abnormalities of the RV can be reliably described by echocardiography but due its complex geometrical shape, echocardiographic assessment of RV function is more challenging. Newer promising echocardiographic techniques are emerging but lack of validation and limited normal reference data influence their routine clinical application. Cardiac magnetic resonance is generally considered the clinical reference technique due to its unlimited imaging planes, superior image resolution, and three-dimensional volumetric rendering. The accuracy and reliability of CMR measurements make it the ideal tool for serial examinations of RV function. Multidetector computed tomography (MDCT) plays an important role in the diagnosis of pulmonary emboli but can also be used for assessing RV ischaemic disease or as an alternative for CMR if contra-indicated. Radionuclide techniques have become more obsolete in the current era. The different imaging modalities should be considered complimentary and each plays a role for different indications.