Correlation of the Myocardial Viability Score with Left Ventricular Ejection Fraction in Patients after Revascularization

Background. Coronary artery disease (CAD) is one of the main causes of cardiovascular death. The severity of CAD is determined by the left ventricular (LV) dysfunction which is caused by coronary atherosclerosis. The possibility of restoring functional capacity of the heart (ejection fraction (EF)) depends on hibernating volume of the myocardium which is a pitfall in revascularization. The aim. To assess the correlation between the score of the viable myocardium (VM) and EF with systolic dysfunction and preserved LVEF in patients after coronary artery bypass grafting (CABG). Material and methods. To implement the set clinical tasks, 62 patients with CAD with preserved systolic function and systolic dysfunction were examined, 35 (56%) patients had heart failure with an EF of 49% (group 2) and less. Twenty-seven (44%) patients had preserved ventricular function of 50% or more (group 1). The mean age of the subjects was 59.6 ± 8.2 years. Five (8.0%) patients denied myocardial infarction. Myocardial scintigraphy was performed on Infinia Hawkeye all purpose imaging system (GE, USA) with integrated CT. The studies were performed in SPECT and SPECT/CT with ECG synchronization (gated SPECT) modes. 99mTc-MIBI with an activity of 555–740 MBq was used. Myocardial scintigraphy was performed in the course of treatment (before CABG and after CABG) according to the One Day Rest protocol. A total of 124 scintigraphic studies were performed. Results and discussion. Samples of the studied patients “before” and “after” treatment were compared using Wilcoxon matched-pairs test. In group 1 in patients with EF ≥ 50% the score of VM increased after CABG with values from 81.7 CI 95% [78.5; 84.9] to 86.9 CI 95% [84.4; 89.3]. However, the EF itself before and after treatment remained the same or slightly decreased amounting to 54.9 CI 95% [50.8; 59.1] and 52.5 CI 95% [48.6; 56.3]. In group 2 in patients with EF ≤ 49% the amount of VM increased after CABG with values from 59.9 CI 95% [54.9; 64.8] to 65.9 CI 95% [60.2; 71.6] (p = 0.00005). However, the EF itself before and after treatment remained the same, amounting to 28.9 CI 95% [24.8; 32.9] and 31.1 CI 95% [26.8; 35.5] (p = 0.19). Conclusions. Myocardial viability in both study groups significantly improved, given the high statistical reliability of the results, although LVEF either remained unchanged or changed slightly. Improvement of static parameters (wall perfusion) also confirms positive effect of revascularization with constant dynamic parameters (EF, end-diastolic volume) or statistically insignificant changes thereof. There is no direct correlation between VM and EF.

Dynamic planar scintigraphy for the rapid kinetic measurement of myocardial 123I-MIBG turnover can identify Lewy body disease

Background Using two static scans for 123I-meta-iodobenzyl-guanidine (123I-MIBG) myocardial scintigraphy ignores the dynamic response from vesicular trapping in nerve terminals. Moreover, the long pause between scans is impractical for patients with Lewy body diseases (LBDs). Here, we optimized indices that capture norepinephrine kinetics, tested their diagnostic performance, and determined the differences in 123I-MIBG performance among disease groups. Methods We developed a new 30-min protocol for 123I-MIBG dynamic planar imaging for suspected LBD patients. Pharmacokinetic modelling of time-activity curves (TACs) was used to calculate three new indices: unidirectional uptake of 123I-MIBG to vesicular trapping (iUp), rate of myocardial 123I-MIBG loss (iLoss), and non-specific fractional distribution of 123I-MIBG in the interstitial space. We compared the performance of the new and existing indices with regard to discrimination of patients with or without LBDs. Subgroup analysis was performed to examine differences in 123I-MIBG turnover between patients in a dementia with Lewy bodies (DLB) group and two Parkinson’s disease (PD) groups, one with and the other without REM sleep behaviour disorder (RBD). Results iLoss was highly discriminative, particularly for patients with low myocardial 123I-MIBG trapping, and the new indices outperformed existing ones. ROC analysis revealed that the AUC of iLoss (0.903) was significantly higher than that of early HMR (0.863), while comparable to that of delayed HMR (0.892). The RBD-positive PD group and the DLB group had higher turnover rates than the RBD-negative PD group, indicating a potential association between prognosis and iLoss. Conclusion 123I-MIBG turnover can be quantified in 30 min using a three-parameter model based on 123I-MIBG TACs. The discriminatory performance of the new model-based indices might help explain the neurotoxicity or neurodegeneration that occurs in LBD patients.

PARK2 Patient Presenting with Dopa-Responsive Dystonia

We report a 34-year-old female PARK2 patient presenting with dopa-responsive dystonia (DRD). She noticed difficulty in raising her foot while walking at the age of 24. Her lower limb symptoms were identified as dystonia later, and she was started on Menesit, which resulted in improvement of her symptoms. She was diagnosed as DRD and has been on continuous treatment since then. The specific binding ratio (SBR) of ¹²³I FP-CIT SPECT was significantly lower than those of controls of the same age, but ¹²³I-meta-iodobenzylguanidine myocardial scintigraphy showed a normal heart to mediastinum ratio. The Montreal Cognitive Assessment, Japanese version, was normal for her age. DRD is an inherited dystonia that typically begins during childhood and may be caused by mutations of the GCH1 (GTP cyclohydrolase), SPR (sepiapterin reductase), or TH (tyrosine hydroxylase) genes. Our patient was diagnosed as PARK2, known as autosomal-recessive juvenile Parkinson’s disease, based on genetic analysis. Although there was no family history of the disease, the decrease in SBR of ¹²³I FP-CIT SPECT enabled us to diagnose PARK2 and to differentiate this from DRD due to other genetic disorders.

CORONARY ARTERY FISTULA, WHERE ARE WE NOW?''

In the study “Long-term outcomes following surgical repair of coronary artery fistula in adults”, Wada and associates, retrospectively evaluated 13 consecutive patients that underwent surgical repair of CAF No deaths, significant ST-T changes or CAF-related events were reported in a follow-up period of 66.2 months, and 1 patient showed poor contrast RCA#2 on postoperative coronary CT with a myocardial scintigraphy showing no significant change compared to the preoperative state Coronary artery fistulas (CAF) are rare congenital or acquired malformations in the connection of the coronary vessels, first described by Krause in 1865 (2). They can be classified as coronary-cameral fistulas, which connect coronary arteries with any of the heart chambers, or coronary artery malformations, which connect coronary arteries with systemic or pulmonary vessels. Congenital CAFs are normally a result of abnormal embryological development, acquired CAFs are commonly a result of cardiac traumatic injuries, and iatrogenic CAFs are usually a result of interventional cardiac procedures. This condition is still highly undiagnosed, as around 75% of incidentally-found CAFs are small and clinically silent, but it is estimated that CAFs are present in about 0.9% of the general population In our experience, we have a CAF incidence of 0.05% in 10,000 cardiac surgeries, which have demonstrated beneficial outcomes of the surgical repair of CAFs in adults . Authors of this article must be congratulated for the successful development of the study and for the contributions to the literature on this rare condition

Complete surgical revascularization: different definitions, same impact?

Objectives: There are several different definitions of complete revascularization on coronary surgery across the literature. Despite the importance of this definition there is no agreement on which one has the most impact. The aim of this study was to evaluate which definition of complete surgical revascularization correlates with early and late outcomes. Methods: All consecutive patients submitted to isolated CABG from 2012 to 2016 with previous myocardial scintigraphy were evaluated. Exclusion criteria: emergent procedures and previous cardiac surgery procedures. Population of 162 patients, follow-up complete in 100% patients; median 5,5 IQR 4,4-6,9 years. Each and all of the 162 patients were classified as complying or not with the four different definitions: Numerical, Functional, Anatomical Conditional and Anatomical unconditional. Univariable and multivariable analyses were developed to detect if any definition was a predictor of perioperative and long-term outcomes. Results: Complete functional revascularization was a predictor of increased survival (HR 0.47 CI95: 0,226-0,969; p=0.041). No other definitions showed effect on follow-up mortality. Age and cardiac dysfunction increased long-term mortality. The definition of complete revascularization did not have an impact on MACCE or need for revascularization Conclusions: An uniformly accepted definition of complete coronary revascularization is lacking. This research raises awareness about the importance of viability guidance for CABG.

Association between neurosarcoidosis with autonomic dysfunction and anti-ganglionic acetylcholine receptor antibodies

Objective To determine whether autonomic dysfunction in neurosarcoidosis is associated with anti-ganglionic acetylcholine receptor (gAChR) antibodies, which are detected in autoimmune autonomic ganglionopathy. Methods We retrospectively extracted cases of sarcoidosis from 1787 serum samples of 1,381 patients between 2012 and 2018. Anti-gAChR antibodies against the α3 and β4 subunit were measured by luciferase immunoprecipitation to confirm the clinical features of each case. We summarized literature reviews of neurosarcoidosis with severe dysautonomia to identify relevant clinical features and outcomes. Results We extracted three new cases of neurosarcoidosis with severe dysautonomia, among which two were positive for anti-gAChR antibodies: Case 1 was positive for antibodies against the β4 subunit, and Case 2 was positive for antibodies against both the α3 and β4 subunits. We reviewed the cases of 15 patients with neurosarcoidosis and severe dysautonomia, including the three cases presented herein. Orthostatic hypotension and orthostatic intolerance were the most common symptoms. Among the various types of neuropathy, small fiber neuropathy (SFN) was the most prevalent, with seven of nine cases exhibiting definite SFN. Six of eight cases had impaired postganglionic fibers, of which the present three cases revealed abnormality of 123I-MIBG myocardial scintigraphy. Of the 11 cases, 10 were responsive to immunotherapy, except one seropositive case (Case 2). Conclusions The presence of gAChR antibodies may constitute one of the mechanisms by which dysautonomia arises in neurosarcoidosis.