Ventricular Infarction Research Articles

English

BACKGROUND A significant number of patients with acute Inferior wall infarction will have RV dysfunction and most of them have occlusion of either right or left circumflex coronary artery. But RV assessment is not done routinely in echocardiographic examination. Patients present with inferior wall myocardial infarction (IWMI) subsequently develop right ventricular myocardial infarction (RVMI) and have poor prognosis. In this study we wanted to evaluate the incidence of RVMI and the role of echocardiography in assessing RV function and its impact in predicting infarct related artery by angiographic analysis in acute IWMI after thrombolysis. METHODS 86 patients with acute IWMI after thrombolysis were randomly selected. Echocardiographic examination of RV function was performed within 72 hours after thrombolysis. We applied RV echo parameters like FAC (Fractional Area Change %), TAPSE (Tricuspid Annular Plane Systolic Excursion), RV S’ (RV Systolic Excursion Velocity) and MPI (Myocardial Performance Index) to assess RV function. 48 patients underwent coronary angiogram which included 10 patients with normal RV function, rest with RV dysfunction. RESULTS Among 86 patients, we compared 64 patients of RV dysfunction with 22 patients having normal function. Echo indices were significantly lower in RV dysfunction group. FAC ( 27 ± 5.95 vs 45 ± 5.4 ) TAPSE (8.5 ± 2.0 19.59 ± 2.8 ), RV S’ ( 5.78 ± 1.26 vs 17.2 ± 3.5 ) and RVMPI (0.22 ± 0.03 vs 0.57± 0.03). Angiographic analysis of 28 of 38 patients with RV dysfunction showed significant proximal lesion in RCA as compared to only 2 among 10 patients with normal RV function. CONCLUSIONS Conventional echo examination will underestimate RV dysfunction hence we applied echo parameters like FAC, TAPSE, RV S’ and RVMPI and a significant proportion of thrombolysed acute IWMI patients were found to have RV dysfunction and it was also helpful in the prediction of infarct related artery which would be predominantly a critical proximal RCA occlusion. KEY WORDS RVMI (Right Ventricular Myocardial Infarction), FAC (Fractional Area Change %), TAPSE (Tricuspid Annular Plane Systolic Excursion), RV S’ (RV Systolic Excursion Velocity) ,MPI (Myocardial Performance Index), IRA ( Infarct Related Artery)

Impact of residual thrombus burden on ventricular deformation after acute myocardial infarction: A sub-analysis from an intravascular optical coherence tomography study.

BackgroundCoronary residual thrombus before stenting in ST-segment elevation myocardial infarction (STEMI) has been linked to microvascular injury but its impact on ventricular deformation and cardiac dysfunction in longer term remains unclear.MethodsThis was a post-hoc sub-analysis from an optical coherence tomography registry. Residual thrombus before stenting was measured geometrically and maximal thrombus-to-lumen area ratio (MTR) was reported. Cardiovascular magnetic resonance (CMR) follow-ups were performed at 30 days post STEMI. The primary outcomes were CMR-derived parameters including left ventricular ejection fraction (LVEF), infarct size, microvascular obstruction (MVO), and left ventricular global strains in radial (GRS), circumferential (GCS), longitudinal (GLS) directions.FindingsFrom March 2017 to March 2019, forty-two patients with first-ever anterior STEMI were included. Average CMR follow-up time was 33 (IQR 30–37) days. In multivariable analysis, MTR was significantly associated with LVEF (per 10%, adjusted β = -1·96, 95%CI -3·66 to -0·26), MVO (per 10%, adjusted β = 0·07, 95%CI 0·01 to 0·13), GRS (per 10%, adjusted β = -1·26, 95%CI -2·28 to -0·23), and GCS (per 10%, adjusted β = 0·53, 95%CI 0·01 to 1·06). However, it was not related to GLS (per 10%, adjusted β = 0·29, 95%CI -0·85 to 1·43) or infarct size (per 10%, adjusted β = 0·07, 95%CI -0·40 to 0·55).InterpretationLarger residual thrombus burden was associated with worse GRS and GCS but not GLS after a first anterior myocardial infarction.FundingThis work was supported by Chinese Academy of Medical Sciences Innovation Fund for Medical Sciences (2016-I2M-1–009), National Natural Science Foundation of China (81,970,308, 81,930,044, and 81,620,108,015), Sanming Project of Medicine in Shenzhen (SZSM201911017), and Shenzhen Key Medical Discipline Construction Fund (No. SZXK001).

Combined protocol for remote ischemic conditioning as the method of cardioprotection in patients with acute ST-segment elevation myocardial infarction

Background. There is currently no commonly accepted strategy for limiting the reperfusion injury that occurs after revascularization in patients with myocardial infarction. This study aimed to investigate the efficacy of a promising cardioprotective method.Material and Methods. Patients with acute anterior ST-segment elevation myocardial infarction (STEMI) (n = 87) were included in an open-label prospective randomized controlled trial. Control group comprised patients with STEMI who underwent only primary percutaneous coronary intervention (PPCI) (n = 44). Patients of intervention group (n = 43) underwent PPCI and remote ischemic perconditioning combined with postconditioning (RIC). The efficacy of RIC was assessed based on cardiac magnetic resonance (CMR) imaging data.Results. The medians of left ventricular (LV) infarct size were significantly higher in patients of control group: 44.8 (33.6; 55.5) versus 52.7 (35.5; 73.9) mL (p = 0.039) at day 10 after STEMI and 34.0 (25.8; 39.8) mL versus 46.0 (32.8; 55.0) mL six months after STEMI in control and intervention groups, respectively (p = 0.004). The groups of patients did not differ in the sizes of area at risk relative to the total LV myocardial volume: 40 (35; 45) and 43 (34; 49)% in control and intervention groups, respectively (р = 0.232). The groups significantly differed in the ratios of infarct size to area at risk: 70.3 (65.1; 86.6)% in control group versus 63.5 (52.7; 72.0)% in intervention group (р = 0.014) as well as in the myocardial salvage indexes: 29.7 (13.5; 34.9)% in control group versus 36.5 (28.0; 47.3)% in intervention group (р = 0.014). The study showed the tendency to greater LV myocardial salvage in intervention group versus control group at six-months follow-up (р = 0.073). The groups significantly differed in the medians of microvascular obstruction volume: 1.9 (1.4; 2.9) mL in intervention group versus 2.5 (1.8; 8.1) mL in control group (p = 0.049) as well as in the proportions of microvascular obstruction in the LV myocardium: 0.94 (0.79; 1.37)% in intervention group versus 1.50 (0.89; 3.66)% in control group (р = 0.046).Conclusion. The RIC method combined with PPCI contributed to the limitation of infarct and microvascular obstruction sizes and was associated with an increase in the myocardial salvage index in STEMI patients.

Left ventricular function, strain, and infarct characteristics in patients with transient ST-segment elevation myocardial infarction compared to ST-segment and non-ST-segment elevation myocardial infarctions.

AimsThis study aims to explore cardiovascular magnetic resonance (CMR)-derived left ventricular (LV) function, strain, and infarct size characteristics in patients with transient ST-segment elevation myocardial infarction (TSTEMI) compared to patients with ST-segment and non-ST-segment elevation myocardial infarctions (STEMI and NSTEMI, respectively).Methods and resultsIn total, 407 patients were enrolled in this multicentre observational prospective cohort study. All patients underwent CMR examination 2–8 days after the index event. CMR cine imaging was performed for functional assessment and late gadolinium enhancement to determine infarct size and identify microvascular obstruction (MVO). TSTEMI patients demonstrated the highest LV ejection fraction and the most preserved global LV strain (longitudinal, circumferential, and radial) across the three groups (overall P ≤ 0.001). The CMR-defined infarction was less frequently observed in TSTEMI than in STEMI patients [77 (65%) vs. 124 (98%), P < 0.001] but was comparable with NSTEMI patients [77 (65%) vs. 66 (70%), P = 0.44]. A remarkably smaller infarct size was seen in TSTEMI compared to STEMI patients [1.4 g (0.0–3.9) vs. 13.5 g (5.3–26.8), P < 0.001], whereas infarct size was not significantly different from that in NSTEMI patients [1.4 g (0.0–3.9) vs. 2.1 g (0.0–8.6), P = 0.06]. Whilst the presence of MVO was less frequent in TSTEMI compared to STEMI patients [5 (4%) vs. 53 (31%), P < 0.001], no significant difference was seen compared to NSTEMI patients [5 (4%) vs. 5 (5%), P = 0.72].ConclusionTSTEMI yielded favourable cardiac LV function, strain, and infarct-related scar mass compared to STEMI and NSTEMI. LV function and infarct characteristics of TSTEMI tend to be more similar to NSTEMI than STEMI.

Diagnostic accuracy of cardiac magnetic resonance tissue tracking technology for differentiating between acute and chronic myocardial infarction.

This study aimed to explore the diagnostic accuracy of cardiac magnetic resonance tissue tracking (CMR-TT) technology in the quantitative evaluation of left myocardial infarction for differentiating between acute and chronic myocardial infarction. A total of 104 human subjects were enrolled in this prospective study. Among them, 64 healthy subjects and 40 patients with left ventricular myocardial infarction and 7 days and 6 months' follow-up CMR studies, including steady-state free precession (SSFP) sequence and late gadolinium enhancement MR imaging, were enrolled. The strain parameters of the infarcted myocardium, its corresponding remote segments, and global right ventricular strain were analyzed using tissue tracking technology, and CMR-TT 3D strain parameters in radial, circumferential, and longitudinal directions were obtained. Receiver operating characteristic (ROC) analysis was used to determine the diagnostic accuracy of the CMR-TT strain parameters for discriminating between acute and chronic myocardial infarction. Peak radial strain (RS) of infarcted myocardium increased from 12.99±7.28 to 18.57±6.66 at 6 months (P<0.001), whereas peak circumferential strain (CS) increased from -8.82±4.71 to -12.78±3.55 (P<0.001). CS yielded the best areas under the ROC curve (AUC) of 0.751 in showing differentiation between acute and chronic myocardial infarction of all the strain parameters obtained. The highest significant differences between acute myocardial infarction and normal myocardium, both in the left and right ventricles, were also found in the RS (P<0.001) and CS (P<0.001). RS and CS obtained by CMR-TT have high sensitivity and specificity in the differential diagnosis of acute versus chronic myocardial infarction, and their use is thus worth popularizing in clinical application.

Prognostic relevance of exercise testing in hypertrophic cardiomyopathy. A systematic review

BackgroundCardiopulmonary exercise test (CPET) is indicated as part of the assessment in hypertrophic cardiomyopathy (HCM) patients and stress echocardiography is often used to assess symptoms. However, the role of exercise testing for prognostic stratification in HCM is still not established. AimsTo systematically review the evidence on the role of exercise testing for prognostic stratification in hypertrophic cardiomyopathy. MethodsA systematic review was conducted for eligible publications, between 2010 and 2020, that included evaluation of outcomes and prognosis. In these studies, patients underwent exercise echocardiography and/or cardiopulmonary exercise testing, performed according to predefined protocols. Diverse parameters were assessed in order to determine which were relevant for the prognosis. Analyzed outcomes included death from any cause, sudden cardiac death (SCD) and equivalents, cardiovascular death, heart failure requiring hospitalization or progression to New York Heart Association classes III or IV, cardiac transplantation, non-sustained ventricular tachycardia, stroke, myocardial infarction and invasive septal reduction therapy. ResultsEighteen publications were included, corresponding to a total of 7525 patients. The mean follow-up period varied between 1 and 8 years. The main findings of these studies revealed that the major predictors of outcomes were abnormal heart rate recovery, abnormal blood pressure response exercise induced wall motion abnormalities, lower peak VO2, higher VE/VCO2, and pulmonary hypertension/exercise-induced pulmonary hypertension. ConclusionAlthough most studies concluded that exercise test results are useful to determine prognosis in HCM, further investigation is needed regarding whether it adds independent value to the current risk stratification strategies.

Role of 2-dimensional speckle tracking echocardiography in diagnosis of right ventricular involvement in patients with inferior wall myocardial infarction undergoing primary percutaneous coronary intervention.

Diagnosis of right ventricular (RV) infarction in the setting of acute inferior wall myocardial infarction (IWMI) has important prognostic implications. We sought to assess the role of 2-D speckle tracking echocardiography (2-D STE) for the assessment of RV involvement in acute IWMI.We included 100 consecutive patients with a diagnosis of recent IWMI, of which 73 had an RCA culprit lesion, undergoing primary percutaneous coronary intervention (PPCI). Patients (n = 73) were classified into 2 groups based on angiographic evidence of RV involvement (lesions proximal to or involving RV branch versus distal lesions). Echocardiographic features of RV dysfunction were assessed using conventional 2-D echocardiographic, and Tissue Doppler parameters as well as 2-D speckle tracking echocardiography.Out of the 73 patients, 42 had RCA lesion proximal to or involving RV branch, while 31 patients had RCA culprit distal to RV branch. Among different parameters assessing RV function, only RV-FWLS was significantly lower among the former group (- 14.2 ± 4.6 vs. - 17.7 ± 4.2, p = 0.026). Receiver-operator characteristic (ROC) analysis showed that RV-FWLS had the strongest discriminatory capability to identify RV infarction (AUC = 0.7, p = 0.02, 95% CI 0.53-0.78). A cut-off value of RV-FWLS ≤ - 20.5% had 88% sensitivity and 33% specificity for diagnosis of RV infarction.STE-derived RV-FWLS with cutoff ≤ - 20.5% could be a reliable and promising tool for prediction of RV involvement in the setting of acute IWMI, which could guide proper risk stratification and tailored acute management strategy.

Multimodality imaging of the ischemic right ventricle: an overview and proposal of a diagnostic algorithm.

Right ventricular (RV) involvement is frequently detected in patients presenting with acute left ventricular myocardial infarction. The ischemic right ventricle carries a dismal outcome by predisposing the heart to arrhythmic events and mechanical or hemodynamic complications. A comprehensive RV evaluation by multimodality imaging could guide clinical practice but has always been a conundrum for the imagers. Two-dimensional echocardiography is the best first-line tool due to its availability of bedside capabilities. More advanced imaging techniques provide a more comprehensive evaluation of the complex RV geometry but are mostly reserved for the post-acute setting. Three-dimensional echocardiography has improved the evaluation of RV volumes and function. The recent application of speckle-tracking echocardiography to the right ventricle appears promising, allowing the earlier detection of subtle RV dysfunction. Cardiac magnetic resonance imaging is considered the gold standard for the RV assessment. Cardiac multidetector computed tomography could be a reliable alternative. The aim of this review is to focus on the growing importance of multimodality imaging of the ischemic right ventricle and to propose a diagnostic algorithm, in order to reach a comprehensive assessment of this too frequently neglected chamber.

Point-of-Care Thoracic Ultrasonography in Patients With Cirrhosis and Liver Failure.

Point-of-care ultrasonography (POCUS) helps determine liver-related pathologies like an abscess, portal vein or hepatic vein thromboses, presence of ascites, site for pleural or ascitic paracentesis, and guiding biopsies. POCUS is revolutionizing the management of critically ill patients presenting with pneumonia, acute respiratory distress syndrome, acute-on-chronic liver failure, and in the emergency. The objectives of thoracic ultrasonography (TUS) are to aid the clinician in differentiating between pneumonia, effusions, interstitial edema and collections, and in estimating the volume status of patients with liver disease using inferior vena cava dynamic indices. The use of POCUS in patients with cirrhosis has since evolved. It is now widely used to help diagnose volume status, left ventricular diastolic dysfunction, myocardial infarction, and right ventricular dilation due to pulmonary embolism and to determine the causes for weaning failures such as effusions, lung collapse, and pneumothorax. During the Coronavirus Disease 2019 (COVID-19) pandemic, moving patients for computed tomography can be difficult. Therefore, TUS is now essential in liver transplantation and intensive care practice to assess ventilatory pressures, cardiac function, and fluid management. This review indicates the current and optimized use of TUS, offers a practical guide on TUS in the liver intensive care unit (ICU), and presents a diagnostic pathway for determining lung and pleural pathology, resolution of respiratory failure, and aid weaning from mechanical ventilation.

Self-configuring nnU-net pipeline enables fully automatic infarct segmentation in late enhancement MRI after myocardial infarction

PurposeTo fully automatically derive quantitative parameters from late gadolinium enhancement (LGE) cardiac MR (CMR) in patients with myocardial infarction and to investigate if phase sensitive or magnitude reconstructions or a combination of both results in best segmentation accuracy. MethodsIn this retrospective single center study, a convolutional neural network with a U-Net architecture with a self-configuring framework (“nnU-net”) was trained for segmentation of left ventricular myocardium and infarct zone in LGE-CMR. A database of 170 examinations from 78 patients with history of myocardial infarction was assembled. Separate fitting of the model was performed, using phase sensitive inversion recovery, the magnitude reconstruction or both contrasts as input channels.Manual labelling served as ground truth. In a subset of 10 patients, the performance of the trained models was evaluated and quantitatively compared by determination of the Sørensen-Dice similarity coefficient (DSC) and volumes of the infarct zone compared with the manual ground truth using Pearson’s r correlation and Bland-Altman analysis. ResultsThe model achieved high similarity coefficients for myocardium and scar tissue. No significant difference was observed between using PSIR, magnitude reconstruction or both contrasts as input (PSIR and MAG; mean DSC: 0.83 ± 0.03 for myocardium and 0.72 ± 0.08 for scars). A strong correlation for volumes of infarct zone was observed between manual and model-based approach (r = 0.96), with a significant underestimation of the volumes obtained from the neural network. ConclusionThe self-configuring nnU-net achieves predictions with strong agreement compared to manual segmentation, proving the potential as a promising tool to provide fully automatic quantitative evaluation of LGE-CMR.

Pitfall of Isolated Right Ventricular Infarction Caused by Non-Dominant Right Coronary Artery.

Pitfall of Isolated Right Ventricular Infarction Caused by Non-Dominant Right Coronary Artery.

Dimethyl fumarate preserves left ventricular infarct integrity following myocardial infarction via modulation of cardiac macrophage and fibroblast oxidative metabolism

Myocardial infarction (MI) is one of the leading causes of mortality and cardiovascular disease worldwide. MI is characterized by a substantial inflammatory response in the infarcted left ventricle (LV), followed by transition of quiescent fibroblasts to active myofibroblasts, which deposit collagen to form the reparative scar. Metabolic shifting between glycolysis and mitochondrial oxidative phosphorylation (OXPHOS) is an important mechanism by which these cell types transition towards reparative phenotypes. Thus, we hypothesized that dimethyl fumarate (DMF), a clinically approved anti-inflammatory agent with metabolic actions, would improve post-MI remodeling via modulation of macrophage and fibroblast metabolism. Adult male C57BL/6J mice were treated with DMF (10 mg/kg) for 3–7 days after MI. DMF attenuated LV infarct and non-infarct wall thinning at 3 and 7 days post-MI, and decreased LV dilation and pulmonary congestion at day 7. DMF improved LV infarct collagen deposition, myofibroblast activation, and angiogenesis at day 7. DMF also decreased pro-inflammatory cytokine expression (Tnf) 3 days after MI, and decreased inflammatory markers in macrophages isolated from the infarcted heart (Hif1a, Il1b). In fibroblasts extracted from the infarcted heart at day 3, RNA-Seq analysis demonstrated that DMF promoted an anti-inflammatory/pro-reparative phenotype. By Seahorse analysis, DMF did not affect glycolysis in either macrophages or fibroblasts at day 3, but enhanced macrophage OXPHOS while impairing fibroblast OXPHOS. Our results indicate that DMF differentially affects macrophage and fibroblast metabolism, and promotes anti-inflammatory/pro-reparative actions. In conclusion, targeting cellular metabolism in the infarcted heart may be a promising therapeutic strategy.

Sympathetic Activation and Arrhythmogenesis after Myocardial Infarction: Where Do We Stand?

Myocardial infarction often leads to progressive structural and electrophysiologic remodeling of the left ventricle. Despite the widespread use of β-adrenergic blockade and implantable defibrillators, morbidity and mortality from chronic-phase ventricular tachyarrhythmias remains high, calling for further investigation on the underlying pathophysiology. Histological and functional studies have demonstrated extensive alterations of sympathetic nerve endings at the peri-infarct area and flow-innervation mismatches that create a highly arrhythmogenic milieu. Such accumulated evidence, along with the previously well-documented autonomic dysfunction as an important contributing factor, has stirred intense research interest for pharmacologic and non-pharmacologic neuromodulation in post-infarction heart failure. In this regard, aldosterone inhibitors, sacubitril/valsartan and sodium-glucose cotransporter type 2 inhibitors have shown antiarrhythmic effects. Non-pharmacologic modalities, currently tested in pre-clinical and clinical trials, include transcutaneous vagal stimulation, stellate ganglion modulation and renal sympathetic denervation. In this review, we provide insights on the pathophysiology of ventricular arrhythmogenesis post-myocardial infarction, focusing on sympathetic activation.

The Efficacy of Thrombolytic Therapy in Inferior Myocardial Infarction with Damage to the Right Ventricular

Aim. To study the results of thrombolytic therapy and accuracy of electrocardiographic assessment of thrombolysis efficiency in inferior myocardial infarction with and without right ventricular lesion.Material and methods. The118 patients with inferior myocardial infarction were included in this study. They received TLT in the first 12 hours of the disease. The dynamics of ST-segment in 90 minutes from the TLT start and coronary angiography data were analyzed.Results. Right ventricular myocardial infarction (RVMI) was diagnosed in 49 (41.5%) of 118 patients by echocardiography. Patients with and without RVMI did not differ in age, gender and comorbidities, but patients with RVMI were more likely to have arterial hypotension, atrioventricular block, and atrial fibrillation. All patients with RVMI had occlusion of the right coronary artery (RCA) in the proximal (34.7%) or medial segment (65.3%). Occlusion of the circumflex coronary artery was found in 20 (29.0%) patients without RVMI, and RCA occlusion - in other patients. The infarction-associated artery blood flow equal TIMI 2-3 was found in 17 (34.7%) patients with RVMI and in 46 (66.7%) patients without RVMI (p&lt;0.005). ST-segment decrease by 50% or more in 90 minutes from the TLT was found in 35 (71.4%) patients with RVMI and in 49 (71.0%) patients without RVMI (p&gt;0.05). The false-positive assessment of thrombolysis efficiency was noted in patients with and without RVMI in 21 (42.9%) and 11 (15.9%) cases (p &lt;0.005), respectively. There were no false-positive assessments in patients with RVMI when using ST-segment decrease to the isoline.Conclusion. TLT should be considered effective in patients with inferior myocardial infarction with the right ventricle lesion, if ST-segment decreases to isoline in 90 minutes from the TLT start.

Factors associated with temporary pacing insertion in patients with inferior ST-segment elevation myocardial infarction.

BackgroundHigh-degree atrioventricular block (HAVB) is a prognostic factor for survival in patients with inferior ST-segment elevation myocardial infarction (STEMI). However, there is little information about factors associated with temporary pacing (TP). The aim of this study was to find factors associated with TP in patients with inferior STEMI.MethodsWe included 232 inferior STEMI patients, and divided those into the TP group (n = 46) and the non-TP group (n = 186). Factors associated with TP were retrospectively investigated using multivariate logistic regression model.ResultsThe incidence of right ventricular (RV) infarction was significantly higher in the TP group (19.6%) than in the non-TP group (7.5%) (p = 0.024), but the incidence of in-hospital death was similar between the 2 groups (4.3% vs. 4.8%, p = 1.000). Long-term major adverse cardiovascular events (MACE), which were defined as a composite of all-cause death, non-fatal myocardial infarction (MI), target vessel revascularization (TVR) and readmission for heart failure, were not different between the 2 groups (p = 0.100). In the multivariate logistic regression analysis, statin at admission [odds ratio (OR) 0.230, 95% confidence interval (CI) 0.062–0.860, p = 0.029], HAVB at admission (OR 9.950, 95% CI 4.099–24.152, p<0.001), and TIMI-thrombus grade ≥3 (OR 10.762, 95% CI 1.385–83.635, p = 0.023) were significantly associated with TP.ConclusionStatin at admission, HAVB at admission, and TIMI-thrombus grade ≥3 were associated with TP in patients with inferior STEMI. Although the patients with TP had the higher incidence of RV infarction, the incidence of in-hospital death and long-term MACE was not different between patients with TP and those without.

An evaluation of medication optimisation following myocardial infarction within a cardiac rehabilitation service

Background/Aims Managing patients' medical risk is a core component of cardiac rehabilitation. However, the optimisation of medical therapy for patients post myocardial infarction has frequently been found to be suboptimal. This article evaluates the evidence-based prescribing practice for patients post myocardial infarction who attended a local cardiac rehabilitation service that included an advanced cardiac rehabilitation nurse. The focus is on dose optimisation of angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists and beta-blocker therapies. Methods Data were collected retrospectively from 100 patient records at a cardiac rehabilitation service. Explored variables included demographic factors, prescribing rates at hospital discharge, left ventricular function, drug types and doses, and drug optimisation rates and timings. Data regarding the practitioner who carried out the optimisation and any documented reasons for not pursuing further dose titration were also collected. Results The advanced cardiac rehabilitation nurse was well placed to optimise pharmacotherapy post myocardial infarction, although the optimisation process was found to be complex, often requiring an overlapping multidisciplinary team approach. Conclusions Care should be taken not to overlook patients with normal left ventricular function or mild left ventricular impairment post myocardial infarction. More advanced practitioner roles are needed to allow the team to take responsibility for the medication optimisation of all patients post myocardial infarction within the cardiac rehabilitation service. The optimisation time target set by the National Institute for Health and Care Excellence was not always reached, as it was not always feasible to safely optimise medications so quickly.

Invasive assessment of fluid therapy in hypotensive patients of postinferior wall myocardial infarction complicated by right ventricular infarction

Background: Management of such patients with inferior wall myocardial infarction (IWMI) complicated by right ventricular myocardial infarction (RVMI) requires volume replacement along with the standard therapy. However, the optimum amount of fluid needed to maintain systolic blood pressure (SBP) ≥90 mmHg in such patients has not been reported yet. This study evaluates the role of graded fluid infusion in improving the hemodynamic parameters in patients of IWMI with RVMI in hypotension or shock and also optimizes the amount of fluid needed to maintain SBP ≥ 90 mmHg. Materials and Methods: In this single-center, prospective observational study, patients with first episode of acute coronary syndrome diagnosed as IWMI complicated by RVMI and SBP &lt;90 mmHg were included. The hemodynamic parameters such as heart rate, SBP, cardiac output, cardiac index, and pulmonary capillary wedge pressure (PCWP) were measured at the baseline and after each 500 ml normal saline over 15 min until SBP ≥ 90 mmHg was attained. The primary objective was to study the change in cardiac output, cardiac index, and PCWP with response to fluid. The amount of fluid needed for ≥ 10 rise in cardiac output and to maintain SBP ≥ 90 mmHg was also evaluated. The secondary objectives were to study the need for inotropic support, complications such as inhospital mortality, acute pulmonary edema, and local site bleeding. Further, the predictors of early responders (&lt;2 L of fluid) were also evaluated. Results: Among all 16 patients, 3 (18.7%) were excluded and the rest received graded fluid therapy. Invasively monitored and graded fluid therapy resulted a significant rise in cardiac output (2.1 ± 0.7 L/min vs. 3.7 ± 0.7 L/min), cardiac index (1.3 ± 0.3 L/min/m2 vs. 2.4 ± 0.76 L/min/m2), and PCWP (8.4 ± 3.0 mmHg vs. 17.6 ± 1.5 mmHg) in comparison to baseline parameters. On an average, 865 ± 462 mL fluid infusion was required for 10% improvement in CO from baseline. However, 2192 ± 560 mL fluid was needed for consistent maintenance of SBP ≥ 90 mmHg. The effect of fluid therapy was not significantly correlated with baseline clinical and hemodynamic parameters. There were no procedure- and therapy-related complications reported during the study. Conclusions: Early response to fluid therapy within 2 L of normal saline occurred independently of baseline hemodynamic parameters. However, more studies with larger number of patients would be needed to confirm the same.

CD38 Genetic Knockout Confers Marked Protection Against In Vivo Myocardial Ischemia/Reperfusion Injury

Background CD38 is a multifunctional membrane protein with the major NAD(P)ase activity in human tissues. It is highly expressed in endothelial cells and some inflammatory cells. Using ex vivo perfused hearts and cell models, we have shown that ischemia/reperfusion (I/R) in the heart leads to CD38 activation with subsequent NAD(P)H depletion and impaired endothelial nitric oxide synthase function, triggering diminished coronary flow and decreased contractile function. Here we test if genetic knockout (KO) of CD38 protects against in vivo myocardial I/R in mice. Methods Male CD38 KO (n=7) and wild type (WT) mice (n=11) in C57BL/6 background were subjected to I/R surgery at the age of 12–16 weeks. The mice were anesthetized, endotracheal intubated, and ventilated with a rodent ventilator. A left lateral thoracotomy was performed, and the left anterior descending coronary artery was visualized and ligated with a slip knot. Then, mice were subjected to 30 minutes of ischemia followed by 24 h of reperfusion. The left ventricular area at risk (AAR) and infarct areas were visualized by Evans blue and TTC staining, respectively. The hearts were sliced and digitally photographed. Left ventricular AAR and infarct area were contoured using Image J software. (P<0.05) was considered significant in statistical testing. Results In CD38 KO and WT mice the AAR/LV % was similar with values of 56.2±6.8 % and 54.6±4.4 %, respectively. However, CD38 KO mice exhibited marked protection against myocardial I/R injury with decreased infarction. Infarct area/AAR was only 10.3±3.2 % in CD38 KO mice compared to 36.7±6.8 % in WT, p=0.0097. Conclusions Thus, abrogation of CD38 expression was observed to be highly protective against in vivo myocardial I/R injury with major reduction in infarction. As new highly potent CD38 inhibitors have recently been developed, these may hold great promise as therapeutics in the treatment of unstable coronary syndromes and acute myocardial infarction.

Global longitudinal strain improves risk assessment after ST-segment elevation myocardial infarction: a comparative prognostic evaluation of left ventricular functional parameters

AimWe aimed to investigate the comparative prognostic value of left ventricular ejection fraction (LVEF), mitral annular plane systolic excursion (MAPSE), fast manual long-axis strain (LAS) and global longitudinal strain (GLS) determined by cardiac magnetic resonance (CMR) in patients after ST-segment elevation myocardial infarction (STEMI).Methods and resultsThis observational cohort study included 445 acute STEMI patients treated with primary percutaneous coronary intervention (pPCI). Comprehensive CMR examinations were performed 3 [interquartile range (IQR): 2–4] days after pPCI for the determination of left ventricular (LV) functional parameters and infarct characteristics. Primary endpoint was the occurrence of major adverse cardiac events (MACE) defined as composite of death, re-infarction and congestive heart failure. During a follow-up of 16 [IQR: 12–49] months, 48 (11%) patients experienced a MACE. LVEF (p = 0.023), MAPSE (p < 0.001), LAS (p < 0.001) and GLS (p < 0.001) were significantly related to MACE. According to receiver operating characteristic analyses, only the area under the curve (AUC) of GLS was significantly higher compared to LVEF (0.69, 95% confidence interval (CI) 0.64–0.73; p < 0.001 vs. 0.60, 95% CI 0.55–0.65; p = 0.031. AUC difference: 0.09, p = 0.020). After multivariable analysis, GLS emerged as independent predictor of MACE even after adjustment for LV function, infarct size and microvascular obstruction (hazard ratio (HR): 1.13, 95% CI 1.01–1.27; p = 0.030), as well as angiographical (HR: 1.13, 95% CI 1.01–1.28; p = 0.037) and clinical parameters (HR: 1.16, 95% CI 1.05–1.29; p = 0.003).ConclusionGLS emerged as independent predictor of MACE after adjustment for parameters of LV function and myocardial damage as well as angiographical and clinical characteristics with superior prognostic validity compared to LVEF.Graphic abstract

Cardioprotective effect of anisodamine against ischemia/reperfusion injury through the mitochondrial ATP-sensitive potassium channel

Previous clinical studies have shown that anisodamine could improve no-reflow phenomenon and prevent reperfusion arrhythmias, but whether this protective effect is related to the antagonism of the M-type cholinergic receptor or other potential mechanisms is uncertain. The aim of the present study was to investigate the role of the mitochondrial ATP-sensitive potassium channel (mitoK ATP ) in cardioprotective effect of anisodamine against ischemia/reperfusion injury. Anisodamine and 5- hydroxydecanoic acid were used to explore the relationship between anisodamine and mitoK ATP . Using a Langendorff isolated heart ischemia/reperfusion injury model, hemodynamic parameters and reperfusion ventricular arrhythmia were evaluated; in addition, changes in myocardial infarct size, cTnI from coronary effluent and myocardial ultrastructure, as well as ATP, MDA and SOD in myocardial tissues, were detected. In the hypoxia/reoxygenation injury model of neonatal rat cardiomyocyte, cTnI release in the culture medium and levels of ATP, MDA and SOD in cardiomyocytes and mitochondrial membrane potential, were analyzed. Overall, anisodamine could significantly improve the hemodynamic indexes of isolated rat heart injured by ischemia/reperfusion, reduce the occurrence of ventricular reperfusion arrhythmia and myocardial infarction area, and improve the ultrastructural damage of myocardium and mitochondria. The in vitro results demonstrated that anisodamine could improve mitochondrial energy metabolism, reduce oxidative stress and stabilize mitochondrial membrane potential. The cardioprotective effects were significantly inhibited by 5-hydroxydecanoic acid. In conclusion, this study suggests that the opening of mitoK ATP could play an important role in the protective effect of anisodamine against myocardial ischemia/reperfusion injury.