Residual Left Ventricular Dysfunction Research Articles

Calcium/Calmodulin-Dependent Protein Kinase II Delta Inhibition and Ventricular Remodeling After Myocardial Infarction

After anterior ST-segment elevation myocardial infarction (STEMI), left ventricular (LV) remodeling results in heart failure and death. Calcium/calmodulin-dependent protein kinase II delta (CaMKIId) is a key molecular mediator of adverse LV remodeling. To determine whether NP202, an orally active inhibitor of CaMKIId, prevents LV remodeling in patients after anterior STEMI with early residual LV dysfunction. A randomized, double-blind, placebo-controlled multicenter clinical trial of NP202 vs placebo in patients after primary percutaneous coronary intervention (PCI) for anterior STEMI was performed from November 19, 2015, to August 1, 2018. The study was performed at 32 sites across the US, Australia, and New Zealand. Patients presenting with anterior STEMI who underwent PCI within 12 hours of symptom onset and left ventricular ejection fraction (LVEF) less than 45% on screening echocardiogram 48 hours after primary PCI were included in the study. Baseline cardiovascular magnetic resonance (CMR) imaging was performed within 5 days of the STEMI and before administration of the study drug. Follow-up CMR was performed after 3 months. Data were analyzed from November 19, 2015, to August 1, 2018. Patients were randomly assigned to NP202, 1000 mg, daily for 3 months vs corresponding placebo. The primary end point was change in LV end-systolic volume index (LVESVi) on CMR. Secondary end points were change in LV end-diastolic volume index, change in LVEF, change in infarct size, and change in diastolic function. Safety and tolerability were also assessed. A total of 147 patients (mean [SD] age, 58 [11] years; 129 men [88%]; 130 White patients [88%]) who experienced anterior STEMI treated with primary PCI were randomized to receive NP202 (73 [49.7%]) or placebo (74 [50.3%]). Baseline LVEF was similar between groups. At baseline, patients randomized to NP202 had greater LVESVi (48.2 mL/m2) than that in the placebo group (41.3 mL/m2; P = .03). However, the groups were otherwise well matched. For the primary end point of change in LVESVi from baseline to 3 months, there was no significant difference between the placebo (median [interquartile range] change, -0.60 [-9.28 to 5.99] mL/m2) and NP202 groups (-3.53 [-9.24 to 4.81] mL/m2) (P = .78). There was also no difference in the secondary efficacy end points assessed by CMR. NP202 was well tolerated and demonstrated an acceptable safety profile. Major adverse cardiac and cerebrovascular event rates were similar between groups. Two deaths occurred in each group during the follow-up period. Three months of treatment with NP202 after primary PCI for anterior STEMI with residual LV dysfunction did not improve LV remodeling. The drug was safe and well tolerated. ClinicalTrials.gov Identifier: NCT02557217.

Therapeutic Plasma Exchange for Treatment of Heparin Induced Thrombocytopenia in a Patient Undergoing Left Ventricular Assist Device Implantation

Introduction Heparin-induced thrombocytopenia (HIT) is an autoimmune reaction to heparin exposure that is associated with a high morbidity and mortality. HIT occurs when platelet factor 4 (PF4) antibodies are released and bind to exogenous heparin. This creates complexes that may induce a life-threatening systemic coagulopathy. Standard treatment for HIT includes discontinuation of heparin and administration an alternative thrombin inhibitor. We report a case of a man who developed HIT prior to left ventricular assist device (LVAD) implantation, a procedure which requires a large dose of intraoperative heparin. The patient was treated with therapeutic plasma exchange (TPE) and was able to safely undergo LVAD implantation. Case Report A 52-year-old Caucasian man was initially admitted for a delayed presentation ST elevation myocardial infarction. He underwent left anterior descending coronary artery (LAD) stent placement and was discharged home on appropriate medical therapy but with significant residual left ventricular dysfunction. The patient returned three weeks later in cardiogenic shock requiring emergent extracorporeal membrane oxygenation (ECMO) placement with a heparin drip per protocol. He was weaned off ECMO and transitioned to Impella support. Labs for thrombocytopenia revealed HIT which was confirmed with a positive serotonin release assay (SRA). For refractory shock and an echocardiogram which showed an ejection fraction of 10-15%, the patient was approved for durable LVAD implantation. TPE was initiated to remove the PF4 antibodies. Using optical density as a guide, the patient underwent five rounds of TPE until he was SRA negative. He then uneventfully received heparin during LVAD implantation. Post procedure, the patient was started on argatroban with warfarin until his INR was therapeutic. The patient was discharged one-month post procedure. He has completed a course of rehab and is now functionally class I with plans for a transplant evaluation. Summary To our knowledge this is the first case report of the use of optical density guided TPE for HIT in a patient undergoing LVAD implantation. The treatment required a multidisciplinary approach and led to an excellent outcome in a critically ill patient.

Characterization and long-term outcomes of patients with myocarditis: a retrospective observational study.

IntroductionThere is limited data on the long-term follow-up of patients with myocarditis.AimTo investigate the long-term follow-up of patients with myocarditis.Material and methodsWe performed a retrospective observational analysis on the clinical long-term outcomes of patients with myocarditis over a 10-year period. The primary outcome was mortality. We identified risk factors for mortality and adverse clinical outcomes. We also compared the characteristics and outcomes of patients presenting with fulminant myocarditis to those presenting with non-fulminant myocarditis.ResultsBetween May 2004 and December 2014, 203 patients with myocarditis or perimyocarditis were admitted to our center. Most patients were male (87.7%) with a median age at presentation of 33 years (interquartile range: 25.4–38.9). The median follow-up period was 56.9 months (interquartile range 25.3–87.3 months), during which the overall mortality was 4.4% (9 patients). Fifteen patients presented with fulminant myocarditis. After multivariable analysis, older age (HR = 1.11, 95% CI: 1.05–1.16, p < 0.001) and a poorer New York Heart Association (NYHA) function class (HR = 4.6, 95% CI: 1.18–18, p = 0.028) were found to be independently associated with a higher risk of mortality, whereas higher albumin levels at presentation (HR = 0.2, 95% CI: 0.07–0.56, p = 0.002) were associated with decreased mortality. The group presenting with fulminant myocarditis had a more severe course of disease and a higher in-hospital mortality (13.3% vs. 0%, p = 0.005).ConclusionsThe overall prognosis of patients with myocarditis is good – in terms of both survival and recovery without residual left ventricular dysfunction.

Clinical characteristics and long-term outcomes of peripartum takotsubo cardiomyopathy and peripartum cardiomyopathy.

AimsAlthough some peripartum‐associated cardiomyopathy patients present with features that are clinically and echocardiographically similar to those of takotsubo cardiomyopathy (TCM), little is known about the diagnosis and clinical course of peripartum TCM.Methods and resultsIn a tertiary hospital in Seoul, Korea, we searched the hospital database to find cardiomyopathy cases that were associated with pregnancy from January 1995 to May 2019. Applying the published diagnostic criteria, we sought peripartum cardiomyopathy (PPCM) and peripartum TCM patients for comparison. Of 31 pregnancy‐associated cardiomyopathy patients, 10 cases of peripartum TCM and 21 cases of PPCM were found. Maternal near‐miss death was significantly more common in the peripartum TCM group than in the PPCM group (100.0% vs. 57.1%, P = 0.030). Complete recovery was observed with all peripartum TCM cases, while 23.8% of the PPCM cases had residual left ventricular dysfunction. One death and one heart transplantation occurred in the PPCM group, while neither occurred in the peripartum TCM group. There was no difference between the two groups in terms of the rate of major adverse clinical events at 3 years of follow‐up [PPCM group: 26.3% (5/19) vs. TCM group: 33.3% (3/9), P = 0.750].ConclusionsOne‐third of pregnancy‐associated cardiomyopathy patients had peripartum TCM. With contemporary supportive care, both PPCM and peripartum TCM patients had a low mortality rate and excellent long‐term outcomes.

COVID-19-Related Multisystem Inflammatory Syndrome in Children Affects Left Ventricular Function and Global Strain Compared with Kawasaki Disease

COVID-19-Related Multisystem Inflammatory Syndrome in Children Affects Left Ventricular Function and Global Strain Compared with Kawasaki Disease

P1265 A home for two: a case of a twin pregnancy complicated by twin-to-twin transfusion in a woman with a repaired total anomalous pulmonary venous connection

Abstract BACKGROUND Total anomalous pulmonary venous connection (TAPVC) is a rare correctable congenital heart lesion. According to the modified World Health Organization classification (mWHO) of maternal cardiovascular risk, pregnant patients with successfully repaired TAPVC are at low cardiovascular risk (mWHO class I), but the risk rises to mWHO class III if left ventricular (LV) impairment and ventricular arrhythmias are present. CASE SUMMARY A 34 years old woman with corrected supracardiac TAPVC, pregnant with a spontaneous monochorionic diamniotic twin pregnancy (TP) complicated by twin-to-twin transfusion syndrome (TTTS) was referred to the cardiologist in preparation for fetoscopic laser coagulation (FLC). She was born with a TAPVC to the innominate vein associated with an atrial septal defect (ASD), repaired at the age of 3 months by anastomosing the PVC to the posterolateral wall of the left atrium and closure of the ASD with a pericardial patch. At follow up a few years later she developed asymptomatic mild LV dysfunction and alternating brady and tachyarrhythmias including non-sustained ventricular tachycardias (NSVT). At 17th weeks of gestation she presented mild dyspnoea (NYHA functional class II) and an alternance of sinus bradycardia, atrial fibrillation and NSVT. 2D echocardiography showed moderate LV dilatation and dysfunction (LVEF 47%). She was treated with loop-diuretics, but refused antiarrhythmic and anticoagulant therapy. At 19th weeks, TTTS was diagnosed and successful FLC of placental anastomoses was carried out. Symptomatic worsening of LV function and functional class developed in the ensuing weeks (NYHA III, LVEF 40%). Induction of foetal lung maturity with maternal administration of steroids was carried out at 28 weeks but stopped because of spontaneous preterm labour. After delivery, the arrhythmic burden increased to the point of requiring admission to the intensive care unit (ICU) where pacemaker implant was indicated, but refused by the patient. Diuretics and ACE-inhibitors were titrated, but no beta-blockers nor other antiarrhythmics could be started due to intermittent av block. At discharge, the patient was asymptomatic at rest and there were no clinical signs of heart failure. At 17 months of follow-up, she was still asymptomatic, though LV function remained poor. The 2 newborns were discharged after a stormy 4 months in the neonatal ICU and are still being treated for bronchopulmonary dysplasia and the sequels of intraventricular haemorrages. DISCUSSION We are not aware of other described twin pregnancies in repaired TAPVC with residual LV dysfunction and arrhythmia. As the haemodynamic load of twin pregnancy is more severe and the twin pregnancy itself at high risk both for prematurity and maternal cardiac deterioration, evaluation by a Specialist Multidisciplinary referral Unit should occur before conception especially in mNYHA class III and higher, as per current guidelines. Abstract P1265 Figure. Image 1

A Population-based Study of Peripartum Cardiomyopathy in Southern Israel: Are Bedouin Women a New High-risk Group?

ObjectivesPeripartum cardiomyopathy (PPCM) is a serious complication of pregnancy. Studies investigating the risk factors that worsen outcomes have yielded conflicting results. The goals of this study were to describe the clinical and echocardiographic characteristics of PPCM in a single tertiary center and to determine the prognostic factors associated with persistence of left ventricular (LV) dysfunction in these women.Study DesignThis retrospective cross-sectional population-based cohort study included all patients with PPCM confirmed by echocardiography who delivered at our center from 2004 to 2014. Two groups were compared to determine long-term maternal outcome: (1) those who recovered normal LV function; and (2) those with residual systolic LV dysfunction.ResultsThere were 148,994 deliveries during the study period. Of these, 89,196 patients were Bedouin and 59,798 were non-Bedouin. Forty-six patients met the PPCM study inclusion criteria. The PPCM prevalence for the total deliveries was 1:3,239. The PPCM prevalence among Bedouin patients was 1:2,787 versus non-Bedouin patients of 1:4,983 (P=0.037). None of the women had pre-existing chronic hypertension, and there was no maternal death. Patients who had severe or moderate LV dysfunction at the clinical presentation of PPCM were less likely to regain normal LV function than those with mild dysfunction (81.2% versus 56.7%, P=0.009). Based on initial echocardiogram, a trend toward residual LV dysfunction was noted in patients with a dilated left ventricle as compared to those with a non-dilated left ventricle (18.8% versus 6.7%, P=0.32). A hypokinetic right ventricle was found in 15.2% of the women who suffered from PPCM.ConclusionIn our cohort, Bedouin women may be at increased risk for PPCM, and patients with severe LV dysfunction have a lower chance of recovery from PPCM.

Secundum Atrial Septal Defect Before and After Surgery

Twenty patients with secundum atrial septal defect, who had undergone open heart surgery were studied retrospectively. Girls were more affected than boys; the sex ratio was 1.5:1. Associated cardiac defects were diagnosed in two patients, one with moderate valvular pulmonic stenosis and the other one with small ventricular septal defect. Typical clinical findings consisted of loud first heart sound, widely fixed split second heart sound and soft ejection systolic murmur at the upper left sternal border were heard in all cases. Mid diastolic murmur due to relative tricuspid stenosis was detected in most cases (75%). Electrocardiographic findings included right axis deviation, prolonged PR-interval and right atrial enlargement were found in 50%, 15% and 60% of cases, respectively. Incomplete right bundle branch block and right ventricular enlargement were found in all cases, as was cardiomegaly with increased vascular markings were found in all cases. Paradoxical ventricular septal motion and visualization of the atrial septal defect were seen in 95% and 75% of cases, respectively. Cardiac catheterization was performed in 19 patients (95%). The pulmonary-systemic flow ratio (Qp/Qs) ranged from 1.7 to 6.3 (mean 2.9 +/- 0.67), and was correlated to the presence of mid diastolic tricuspid flow murmur and paradoxical ventricular septal motion. Simple closure of the defect was the procedure of choice, but in one patient (5%) pericardial patch was used to close the very large defect. The mortality rate was 10 per cent. Physical retardation was found in all boys and 50% of girls, before surgery. Body weight percentile increased in most cases (61.1%), while body height percentile increased in only 5.6% of cases, postoperatively. Ejection systolic murmur at the upper left sternal border was still detected in one patient (5.6%). Incomplete right bundle branch block persisted in all cases, while cardiomegaly was still found in 5.6% of cases followed-up six months to five years after surgery. There was no residual left ventricular dysfunction in all cases.

Fulminant myocarditis: Characteristics, treatment, and outcomes.

Myocarditis is an inflammatory disease of the myocardium with a broad spectrum of clinical presentations, ranging from mild symptoms to severe heart failure. The course of patients with myocarditis is heterogeneous, varying from partial or full clinical recovery in few days to advanced low cardiac output syndrome requiring mechanical circulatory support or heart transplantation. Fulminant myocarditis (FM) is a peculiar clinical condition and is an acute form of myocarditis, whose main characteristic is a rapidly progressive clinical course with the need for hemodynamic support. Despite the common medical belief of the past decades, recent comprehensive data, including a recent registry that compared FM with acute non-FM, highlighted that FM has a poor inhospital outcome, often requires advanced hemodynamic support, and may result in residual left ventricular dysfunction in survivors. This review aimed to provide an updated practical definition of FM, including essentials in the diagnosis and management of the disease. Finally, the outcome of FM was critically revised according to the current published registries focusing on the topic.

Structural assessment of myocardial infarction scars and left ventricular function with cardiac magnetic resonance imaging in patients at high risk of sudden cardiac death.

Results of qualitative and quantitative analyses of scars and LV (left ventricle) function acquired by means of cardiac magnetic resonance (CMR) were correlated with a subsequent occurrence of malignant ventricular arrhythmias in patients at high risk of sudden cardiac death (SCD). We have prospectively followed 47 patients (mean age 60 ± 11 years) who were hospitalized for an implantable cardioverter-defibrillator (ICD) implantation to prevent SCD. All post-MI patients had severe residual LV dysfunction (LVEF 33±14%). Patients were examined with CMR. Based on CMR analysis, we evaluated the basic functional parameters of LV as well as mass, volume, transmurality and heterogeneity of the post-MI scar. The patients with malignant arrhythmias were characterized by smaller LV end-diastolic diameters (LVED 192 ± 79 vs 254 ± 47 mm, p = 0.003) and end-systolic diameters (LVES 131 ± 80 vs 181 ± 45 mm, p = 0.01). As for the other observed functional and morphological CMR parameters, no significant differences between the two groups were detected. These results indicate that post-MI patients with severe residual left ventricular dysfunction and dilatation are in the long term characterized by a lower incidence of malignant arrhythmias compared to the patients with less dilated LV with a comparably severe LV dysfunction (Tab. 2, Fig. 3, Ref. 26). Text in PDF www.elis.sk.

Prognosis of myopericarditis as determined from previously published reports.

The prognosis of pericarditis with concomitant myocarditis, especially in the setting of troponin elevation, is a reason for concern because it could imply an adverse outcome. We performed a comprehensive Medline search of all publications from 2000 to 2013 with the MeSH terms 'pericarditis', 'myocarditis' and 'prognosis'. Additional publications were sought using the reference lists of identified papers, the published reviews on this topic, and a search of abstracts from the American Heart Association, American College of Cardiology, and European Society of Cardiology scientific sessions. We identified eight major clinical series evaluating the prognosis of myopericarditis. Studies included a total of 389 patients with myopericarditis (mean age 31.7 years, men-to-women ratio 4.0). After a mean follow-up of 31 months, residual left-ventricular dysfunction was reported in 3.5% without cases of heart failure. Recurrences occurred in 13.0% of cases mainly as recurrent pericarditis (>90%), cardiac tamponade and constrictive pericarditis in less than 1% of cases. The overall prognosis seems good (no mortality), with only one single discordant study reporting three deaths: one related to cardiac tamponade and two sudden cardiac deaths during hospitalization, but no out-of-hospital deaths during follow-up. Myopericarditis has a good overall prognosis. Troponin elevation in this setting does not predict an adverse outcome in most cases. Thus it is important to reassure the patients on their prognosis, explaining the nature of the disease and the likely course. Diagnostic and therapeutic choices should take into account the overall good outcome of these patients, including less invasive diagnostic tools and toxic drugs.

Cardiac troponin-T in acute pericarditis

The long-term outcome of acute pericarditis with high cardiac troponin-T (cTnT) is unknown. Our purpose was to investigate the prognostic and clinical value of cTnT in myopericardial inflammatory syndromes. Between January 2001 and September 2011, 107 patients hospitalized for acute pericarditis or myopericarditis were enrolled. Postinfarction pericarditis and neoplastic pericarditis were excluded. Physical examination, ECG, echocardiography and blood tests were performed. Among the 105 patients (89% men, mean age 36 ± 15 years-old), a cTnT rise was detectable in 64 patients (60.9%). Only younger age was found as an independent factor for higher values of cTnT in multivariate analysis (P = 0.03). After a mean follow-up of 51 months, a similar rate of complications was found in patients with a positive or a negative cTnT test: recurrent pericarditis (11 vs. 19%, P = 0.23) and cardiac tamponade (2 vs. 5%, P = 0.56). No cases of constrictive pericarditis, residual left ventricular dysfunction or hospital death were detected. The left ventricular ejection fraction remained unchanged during the follow-up (62.6 ± 6.5 vs. 61.9 ± 5.8, P = 0.89). In acute pericarditis, a cTnT rise is a frequent finding and commonly found in younger patients. However, unlike acute coronary syndrome, cTnT rise is not a negative prognostic marker.

ICD Implantation and Arrhythmia‐Free Survival in Patients with Depressed LV Function Following Surgery for Valvular Heart Disease

Although prophylactic implantable cardioverter-defibrillator (ICD) implantation is beneficial in patients with severe ischemic cardiomyopathy, it is unclear whether patients with cardiomyopathy due to valvular heart disease have a similar benefit. We followed 17 patients (14 men/three women, age 62 +/- 13 years, left ventricular ejection fraction [LVEF] 29 +/- 10%) who had nonischemic valvular cardiomyopathy, underwent valvular heart surgery (aortic valve replacement, mitral valve replacement, and/or mitral valve repair), and subsequently had an electrophysiology study (EPS), for a median of 2.8 years. These patients were compared with 34 patients with prior myocardial infarction and no significant valvular heart disease, who were matched (1:2) for age, gender, LVEF, EPS result, T-wave alternans result, and ICD placement. Occurrence of arrhythmias was ascertained from ICD device clinic follow-up and vital status was determined using the National Death Index. There were no differences between the groups in overall survival (P = 0.24) or arrhythmia-free survival (P = 0.38), and the 2-year arrhythmia-free survival was 82% for the valvular patients versus 73% for the ischemic patients. Among patients with ICDs, there was no difference between the groups in overall survival (P = 0.34), time to first appropriate ICD therapy (P = 0.54), and arrhythmia-free survival (P = 0.51). Patients with valvular cardiomyopathy and residual left ventricular dysfunction following valvular surgery who underwent a tailored approach to ICD implantation had similar overall and arrhythmia-free survival as patients with ischemic cardiomyopathy.

Autologous Bone-Marrow Stem Cell Support in Acute Anterior Myocardial Infarction.

Purpose- Emerging evidence suggests that stem and progenitor cells derived from bone marrow can improve cardiac function and perhaps outcome in patients after acute myocardial infarction (AMI). In this single-centre randomised trial, we evaluated whether intracoronary transfer of autologous bone-marrow stem cells can affect not only global left ventricular (LV) function (nuclear scintigraphy) but also autonomic control (heart rate variability, HRV) and baroreflex sensitivity (BRS) at 12 months' follow-up.Methods- After successful percutaneous coronary intervention (PCI) for acute ST-segment elevation myocardial infarction and residual LV dysfunction, 33 patients were randomly assigned to either a control group (n=17) that received optimum postinfarction treatment, or a bone-marrow-stem-cell group (n=16) that received optimum treatment plus intracoronary infusion of autologous bone-marrow stem cells 4±1 days after PCI. Test analyses were done by two investigators blinded for treatment assignment.Results- Global LVEF at baseline (determined 3±1 days after PCI) was 36.2±9.4 in controls and 35.1±9.8 in the bone-marrow cell group (P=NS). After 12 months, mean global LVEF had increased by 25% in the control group but 41% in the treated group with an anti-remodeling effect in the latter: LVEDV increased by 12% in the control vs 2% in the treated group (P<0.05). This was associated with improved HRV (SD −20ms vs +644 ms in the treated group P<0.01), particularly in the parasympathetic-related oscillation (HF +85.7±216 ms vs. +289.3±366 ms) and higher BRS (+3.4±11.7 vs +8.7±6.3 ms/mmHg) (control vs treated, P<0.05 in all comparisons). Cell transfer did not increase the risk of adverse clinical events, in-stent restenosis, or proarrhythmic effects. In 12 months follow-up 4 exitus (24%) were observed in the control group vs. only 1 (6%) in the treated groupConclusions- The improvement of left-ventricular systolic function and prognosis in AMI patients by intracoronary transfer of autologous bone-marrow-cells may be mediated by higher vagal tone. (ClinicalTrials.gov number, NCT00437710).

Cardiac troponin i in acute pericarditis

ObjectivesThis study was designed to investigate the prognostic value of cardiac troponin I (cTnI) in viral or idiopathic pericarditis. BackgroundIdiopathic acute pericarditis has been recently reported as a possible cause of nonischemic release of cTnI. The prognostic value of this observation remains unknown. MethodsWe enrolled 118 consecutive cases (age 49.2 ± 18.4 years; 61 men) within 24 h of symptoms onset. A highly sensitive enzymoimmunofluorometric method was used to measure cTnI (acute myocardial infarction [AMI] threshold was 1.5 ng/ml). ResultsA cTnI rise was detectable in 38 patients (32.2%). The following characteristics were more frequently associated with a positive cTnI test: younger age (p < 0.001), male gender (p = 0.007), ST-segment elevation (p < 0.001), and pericardial effusion (p = 0.007) at presentation. An increase beyond AMI threshold was present in nine cases (7.6%), with an associated creatine kinase-MB elevation, a release pattern similar to AMI, and echocardiographic diffuse or localized abnormal left ventricular wall motion without detectable coronary artery disease. After a mean follow-up of 24 months a similar rate of complications was found in patients with a positive or a negative cTnI test (recurrent pericarditis: 18.4 vs. 18.8%; constrictive pericarditis: 0 vs. 1.3%, for all p = NS; no cases of cardiac tamponade or residual left ventricular dysfunction were detected). ConclusionsIn viral or idiopathic acute pericarditis cTnI elevation is frequently observed and commonly associated with young age, male gender, ST-segment elevation, and pericardial effusion at presentation. cTnI increase is roughly related to the extent of myocardial inflammatory involvement and, unlike acute coronary syndromes, is not a negative prognostic marker.

Failure Of An Implantable Left Ventricular Assist Device: A Distinctive Electrocardiographic Pattern Before Malfunction

J thorac Cardiovasc Surg 1998;115:1376-8

Studies on prolonged acute regional ischemia: IV. Aggressive surgical treatment for intractable ventricular fibrillation after acute myocardial infarction

Of 21 dogs undergoing ligation of the left anterior descending coronary artery and 50% stenosis of the left circumflex coronary artery, 15 developed intractable ventricular fibrillation and underwent 1 added hour of femoro-femoral bypass. Three hearts were removed after 1 hour on bypass without myocardial reperfusion for biochemical and mitochondrial analysis. After the 1 hour, five underwent unmodified blood reperfusion on bypass; seven underwent 1 hour of aortic clamping on vented bypass to simulate coronary artery bypass grafting with multidose blood cardioplegic reperfusion. Regional systolic shortening was measured with ultrasonic crystals and cardiac output was measured by thermodilution techniques. All six hearts with no ventricular fibrillation or with reversible ventricular fibrillation and hearts that were not reperfused developed cardiogenic shock (40% decrease in stroke work index, p less than 0.05) because of persistent left ventricular dyskinesia (-40% of systolic shortening, p less than 0.05) and progressive circumflex hypocontractility (48% systolic shortening, p less than 0.05) and showed extensive (68%) triphenyltetrazolium chloride nonstaining. Two dogs died of left ventricular power failure (33% mortality rate). In contrast, 11 of 12 dogs that were reperfused could be weaned from bypass (8% mortality rate). The four dogs surviving after unmodified blood reperfusion (20% mortality rate) showed severe residual left ventricular dysfunction (39% of control stroke work index, p less than 0.05), had equivocal recovery of anterior contractility (10% +/- 7% of systolic shortening), had marginal recovery of contractility in the remote myocardium (60% +/- 11% of systolic shortening), and had extensive triphenyltetrazolium chloride nonstaining (58%). Conversely, all seven dogs with intractable ventricular fibrillation undergoing controlled reperfusion after 4 hours of ischemia recovered normal stroke work index (91%), regained 23% of systolic shortening in the region supplied by the left anterior descending coronary artery (p less than 0.05), 125% of systolic shortening in the circumflex region (p less than 0.05), and showed only 25% triphenyltetrazolium chloride nonstaining (p less than 0.05). These results suggest aggressive treatment of intractable ventricular fibrillation after acute myocardial infarction by providing reperfusion on bypass can salvage hearts thought previously to be damaged irreversibly.(ABSTRACT TRUNCATED AT 400 WORDS)

Left ventricular systolic and diastolic function during acute coronary artery balloon occlusion in humans

Left ventricular function during percutaneous transluminal coronary angioplasty was studied in 16 patients undergoing the procedure. All measurements were performed before and during the first episode of balloon coronary occlusion. In 16 patients (Group A), data were recorded before and 30 or 50 s after balloon inflation, and in 8 of these patients (Group B) data were also recorded 15 min after the complete procedure. Left ventriculograms indicated a marked dyskinesia of the anterior and apical wall in all patients.After balloon inflation, there was a marked depression in stroke index and ejection fraction and an increase in left ventricular end-diastolic pressure and the time constants of relaxation in all patients. Simultaneous recording of left ventricular pressure (Millar micromanometer) during cineangiography permitted the assessment of myocardial and chamber stiffness. Although there was a strong tendency for both myocardial and chamber stiffness to increase after 30 to 50 s of occlusion, these increases were statistically insignificant.In Group B, a third set of angiographic and pressure measurements obtained 15 min after completion of the coronary angioplasty procedure indicated no residual left ventricular dysfunction, and in this respect, the results are of added clinical importance.

Myocarditis and cardiomyopathy

With more widespread application of EMB techniques, a significant percentage of ICCM patients have been found to have lymphocytic myocarditis on biopsy. It is now appreciated that patients with myocarditis may also present with isolated abnormalities of left ventricular diastolic function, dysrhythmias, and/or complaints of chest discomfort with normal coronary angiograms. Epidemiologic and serologic data incriminate a viral etiology underlying many cases of acute myocarditis and ICCM. Although most cases of viral myocarditis appear to resolve without residual left ventricular dysfunction, a small but significant percentage of these patients progress to chronic congestive cardiomyopathy. In the absence of persistent active viral infection in these patients, myocardial damage may be mediated by both cellular and humoral immune mechanisms. The concept of virus-induced immune mediated myocardial damage forms the basis for attempts at immunosuppressive therapy. Whether immunosuppressive therapy alters the natural history of myocarditis is at present unknown and awaits demonstration by a controlled clinical trial.

Pre- and postoperative left ventricular contractile function in patients with aortic valve disease.

In 43 patients left ventricular micromanometry and cineangiography were performed preoperatively and and 20 months after aortic valve replacement. A score of left ventricular functional impairment, derived from 5 to 8 haemodynamic variables, was calculated as: number of pathological indices x 100/total number of determined indices. Preoperatively the score of left ventricular functional impairment amounted to 35 per cent in group 1 (aortic stenosis: n = 19), to 61 per cent in group 2 (combined lesion:n = 15) (P less than 0.05), and to 87 per cent in group 3 (aortic regurgitation: n = 9) (P less than 0.001). In contrast, the functional classification according to the NYHA showed similar impairment in the 3 groups. Postoperatively the score of left ventricular functional impairment decreased significantly in all 3 groups to 10, 16, and 27 per cent, respectively, but the score of group 3 remained raised (P less than 0.05) as compared with that of group 1. The patients with residual left ventricular dysfunction had a higher preoperative left ventricular muscle mass than the patients with normal or near normal postoperative left ventricular function. It is concluded that (1) at similar functional impairment according to the NYHA classification left ventricular contractile function is more severely impaired in aortic regurgitation and in aortic regurgitation + aortic stenosis than in aortic stenosis alone, (2) left ventricular function improves significantly after valve replacement in all three forms of aortic valve disease, (3) residual functional impairment is greater in aortic regurgitation than in aortic stenosis or aortic stenosis + aortic regurgitation, and (4) persistent postoperative left ventricular functional impairment is found in the patients with severe preoperative hypertrophy.