Nondita Sarkar

Effects of intramyocardial injection of phVEGF‐A165 as sole therapy in patients with refractory coronary artery disease – 12‐month follow‐up: Angiogenic gene therapy

Abstract. Sarkar N, Rück A, Källner G, Y‐Hassan S, Blomberg P, Islam KB, van der Linden J, Lindblom D, Nygren AT, Lind B, Brodin L‐Å, Drvota V, Sylvén C (Karolinska Institute, Huddinge University Hospital, Novum, Stockholm, Sweden). Effects of intramyocardial injection of phVEGF‐A165 as sole therapy in patients with refractory coronary artery disease: 12‐month follow‐up. Angiogenic gene therapy. J Intern Med 2001; 250: 373–381.

Myocardial Doppler tissue velocity improves following myocardial gene therapy with VEGF-A165 plasmid in patients with inoperable angina pectoris

BACKGROUND Myocardial tissue velocity and perfusion were studied in patients with severe angina pectoris following gene therapy by intramyocardial injection of phVEGF-A165 via thoracotomy. Plasma concentrations of VEGF-A increased postoperatively. Two months after treatment anginal status and myocardial tissue velocity improved and perfusion showed a tendency to improve. Tissue velocity imaging appears to be a sensitive, objective method for detecting changes in myocardial function following gene therapy. OBJECTIVE To study effects on myocardial tissue velocity and perfusion in patients with angina pectoris following intramyocardial injection of phVEGF-A165 via thoracotomy. DESIGN Open label, phase I/II. METHODS Six patients with Canadian Cardiovascular Society (CCS) angina pectoris functional class III - IV and with major defects at adenosine stress single-photon emission computerized tomography (SPECT) were studied. In addition to SPECT, coronary angiography and dobutamine stress echocardiography with tissue Doppler velocity imaging were performed before and two months after gene transfer. RESULTS Plasma concentrations of VEGF-A increased 2 to 3 times (P < 0.04) over baseline from 2 to 14 days after injection with normalization after 4 weeks. The CCS class improved about 40%, from 3.3 +/- 0.2 to 2.0 +/- 0.3 (P < 0.02) and nitroglycerine consumption decreased 30 - 40%, from 44 +/- 17 to 15 +/- 5 tablets per week (P < 0.05). The maximal systolic myocardial tissue velocity increased in all patients about 25% (P < 0.02) but did not reach the reference range. Myocardial perfusion at SPECT improved in four of the six patients. CONCLUSIONS Anginal status, myocardial tissue velocity and perfusion can be improved by phVEGF-A165 intramyocardial injection. Tissue velocity imaging appears to be a sensitive, objective method for detecting changes in myocardial function following gene therapy.

Nonsurgical direct delivery of plasmid DNA into rat heart: time course, dose response, and the influence of different promoters on gene expression.

Transfer of genes encoding therapeutic proteins into the myocardium shows great potential for treatment of coronary artery disease. To quantitatively elucidate the behavior of plasmid DNA following cardiac gene transfer, time kinetics, dose-response relationship, systemic spread to the liver, and the influence of different promoters on plasmid DNA gene expression in rat hearts were examined using a novel nonsurgical direct delivery method that enables testing of large numbers of animals. Plasmids encoding either vascular endothelial growth factor A 165 or a fusion protein between enhanced green fluorescent protein (EGFP) luciferase were injected directly in rat hearts under echocardiographic guidance. The results show that gene expression is dose related and that the duration of gene expression is transient. These findings underscore the necessity to explore other efficient vectors or alternative methods of gene delivery to achieve increased and prolonged gene expression.

Glycaemic control and restenosis after percutaneous coronary interventions in patients with diabetes mellitus: a report from the Insulin Diabetes Angioplasty study

Objective: We investigated the impact of glucose control on target lesion restenosis after PCI in patients with type 2 diabetes. Methods: Ninety-three consecutive patients with type 2 diabetes accepted for PCI were randomised to intensified glucose control based on insulin (I-group; n=44) or to continue ongoing glucose-lowering treatment (C-group; n=49).The treatment target was a FBG of 5—7 mmol/L and HbA1c <6.5%. Information on target lesion restenosis after six months was available in 82 patients. Results: At baseline HbA1c and FBG did not differ between the I- and C-groups, respectively (HbA1c: 6.5 vs. 6.5%; p=1.0 and FBG: 7.0 vs. 7.3 mmol/L; p=0.3). After six months there was no significant change in HbA1c or FBG in either group (change in HbA1c: -0.2 vs.-0.1%; p=0.3 and in FBG: +0.2 vs. -0.3 mmol/L; p=0.3 in the I- and C-groups, respectively). Target lesion restenosis at six months did not differ, I vs. C = 41 and 44% (p=0.8). Independent predictors for restenosis were previous myocardial infarction (OR 8.0, 95% CI 2.5—25.7; p=<0.001) and FBG at baseline (OR for an increase by 1 mmol/L = 1.4, 95% CI 1.1—1.9; p=0.015). Conclusions: Restenosis was predicted by baseline FBG suggesting that it would be of interest to target glucose normalisation in future trials. Intensified insulin treatment did not influence the rate of restenosis indicating that the main focus should be on lowering glucose rather than the tool to normalise glucose.

Protein and Angiogenic Dose-Response Expression of phVEGF-A165 Gene in Rat Myocardium

Therapeutic myocardial angiogenesis by means of transient overexpression of angiogenic growth factors is a potential treatment modality for severe ischemic heart disease. This study was undertaken in the rat to examine effects of phVEGF-A165 myocardial transfection in terms of dose-response as regards the number of hVEGF-A expressing cells on one hand and on the other angiogenesis. Non-surgical echocardiography-guided intramyocardial injection of phVEGF-A165 was done into normoxic or hypoxic (10[emsp4 ]% O2) rats. Cardiomyocytes expressing VEGF-A protein, capillary morphology and density were determined after 5 days. VEGF protein expression was seen in rat cardiomyocytes located around the tip of the injection scar and increased dose-dependently (p<0.05). Microvessel density also increased dose-dependently with phVEGF165 (p<0.05) and with hypoxia (p<0.05). No vascular tumours were observed. In conclusion, direct intramyocardial injection of phVEGF-A165 in the rat results in a dose-dependent increase both in transfected hVEGF-A protein producing cells and in angiogenesis.

The value of a new cardiac magnetic resonance imaging protocol in Myocardial Infarction with Non-obstructive Coronary Arteries (MINOCA) – a case-control study using historical controls from a previous study with similar inclusion criteria

BackgroundMyocardial Infarction with Non-Obstructive Coronary Arteries (MINOCA) is common with a prevalence of 6% of all patients fulfilling the diagnosis of myocardial infarction. MINOCA should be considered a working diagnosis. Cardiac Magnetic Resonance (CMR) imaging has recently been suggested to be of great value to determine the cause behind MINOCA. The objectives of this paper are to describe the rationale behind the second Stockholm Myocardial Infarction with Normal Coronaries (SMINC-2) study and to discuss the protocol for investigation of MINOCA patients in the light of the recently published position paper from the European Society of Cardiology.MethodsThe SMINC-2 study is an open non-randomised study using historical controls for comparison. The primary aim is to prove that MINOCA patients investigated with the latest CMR imaging technique can achieve a diagnosis in 70% of all cases entirely by imaging. By including 150 patients we will have >80% chance to prove that the diagnostic accuracy can be improved by 20 absolute % with a p-value of less than 0.05 when compared with CMR imaging in the SMINC-1 study. Furthermore, in addition to invasive coronary angiography, coronary arteries are evaluated by computed tomography angiography to investigate coronary causes and questionnaires are used to describe Quality-of-Life (QoL). By January 1st 2017, 75 patients have been included.DiscussionWhether CMR imaging can provide a diagnosis to an adequate proportion of MINOCA patients is unknown. Well-defined inclusion and exclusion criteria will be used to compare a MINOCA cohort from the population with an appropriate control group. Positive results are likely to influence future guidelines of the management of MINOCA. Furthermore, the study will give mechanistic insights into MINOCA in particular in patients with “true” myocardial infarction and describe QoL in this vulnerable group of patients.Trial registrationClinical Trials NCT02318498.