Cardiac fibrosis plays an important prognostic role in nonischemic cardiomyopathy (NICM), making it a potential therapeutic target. Although electromechanical mapping has been used to identify ...myocardial scar and facilitate intramyocardial intervention in the setting of ischemic heart disease, its application has not been described in NICM. We assessed the detection of myocardial fibrosis by endoventricular electromechanical mapping in an experimental model of NICM. The NOGA
®
XP system was used to perform left ventricular mapping in twelve sheep that had undergone intracoronary doxorubicin dosing to induce NICM and in six healthy control animals. Results for endocardial voltage and mechanical shortening were evaluated against myocardial fibrosis burden, as determined by delayed-enhancement cardiac magnetic resonance and quantitative histomorphometry. Doxorubicin treatment resulted in dilated cardiomyopathy with moderate-severe impairment of left ventricular ejection fraction. Late gadolinium uptake was present in 9/12 doxorubicin animals, while histological fibrosis was approximately doubled compared to controls and was distributed multisegmentally throughout the left ventricle. Cardiomyopathy was associated with widespread reductions in unipolar and bipolar voltage amplitude and endocardial shortening. Each parameter showed an inverse relationship with the burden of fibrosis. Moreover, unipolar voltage and linear local shortening ratio displayed moderate accuracy for identifying myocardial segments with delayed contrast enhancement or increased fibrosis content, with optimal discriminatory thresholds of 7.5 mV and 11.5%, respectively. In this model of NICM, electromechanical mapping shows potential for delineating segmental differences in fibrosis. Pending clinical evaluation, it may therefore have applicability for directing targeted intramyocardial interventions in nonischemic heart disease.
Ischemic heart disease, despite advances in treatment, remains the major cause of mortality worldwide. NOGA 3D left ventricular electromechanical mapping allows accurate determination of cardiac ...function and precise identification of sites of injury. In a porcine model of ischemia-reperfusion injury, we validate the use of the NOGA mapping system for assessment of cardiac function along with the Myostar injection catheter for directed delivery of therapeutics to localized target sites in the setting of acute myocardial injury.
Method for delivery remains a central component of stem cell-based cardiovascular research. Comparative studies have demonstrated the advantages of administering cell therapy directly into the ...myocardium, as distinct from infusing cells into the systemic or coronary vasculature. Intramyocardial delivery can be achieved either transepicardially or transendocardially. The latter involves percutaneous, femoral arterial access and the retrograde passage of specially designed injection catheters into the left ventricle, making it less invasive and more relevant to wider clinical practice. Imaging-based navigation plays an important role in guiding catheter manipulation and directing endomyocardial injections. The most established strategy for three-dimensional, intracardiac navigation is currently endoventricular, electromechanical mapping, which offers superior spatial orientation compared to simple x-ray fluoroscopy. Its provision of point-by-point, electrophysiologic and motion data also allows characterization of regional myocardial viability, perfusion, and function, especially in the setting of ischemic heart disease. Integrating the mapping catheter with an injection port enables this diagnostic information to facilitate the targeting of intramyocardial stem cell delivery. This review discusses the diagnostic accuracy and expanding therapeutic application of electromechanical navigation in cell-based research and describes exciting developments which will improve the technology’s sensing capabilities, image registration, and delivery precision in the near future.
To determine the relation between electromechanical endocardial mapping (EEM) and cardiac magnetic resonance (CMR) derived functional and viability parameters in patients with a large myocardial ...infarction.
Forty-two patients with a large ST-elevation myocardial infarction underwent both EEM and CMR four months after primary percutaneous coronary intervention. EEM was performed to assess linear local shortening (LLS), unipolar voltage (UV) and bipolar voltage (BV). CMR cine imaging was performed to determine left ventricular global volumes, ejection fraction and regional function. Late gadolinium enhancement was used to assess size and transmural extent of infarction. Average LLS, UV and BV differed significantly between normal and dysfunctional segments (9.8 vs. 7.3, 11.8 vs. 9.7 and 3.3 vs. 2.8 for LLS, UV and BV respectively; p<0.001 for LLS and UV, p=0.006 for BV). In addition, average LLS, UV and BV, differed significantly between non-, subendocardial and transmural enhanced segments (10.8 vs. 8.8 vs. 5.0, 12.3 vs. 10.5 vs. 9.5 and 3.5 vs. 3.0 vs. 2.3 for LLS, UV and BV, respectively, p<0.001 for all variables). Although regional EEM data showed reasonable correlation with CMR, specific cut-off values for EEM parameters could not be established.
EEM may be helpful in determining both the regional function and the transmural extent of infarction in patients with a large myocardial infarction. However, correlation with CMR parameters was moderate and exact cut-off values for EEM parameters could not be established. Further development of this potentially very useful modality is needed before it can be advocated for exact border-zone endocardial injection.
Since the introduction of percutaneous transluminal angioplasty in the late 1970s the question remains whether myocardial tissue behind an obstruction will benefit from renewed blood supply and if an ...intervention will contribute to a better myocardial function. Positron emission tomography is recognized to be the golden standard in myocardial viability assessment. Recently the three‐dimensional electromechanical NOGA endocardial mapping system was introduced. The system measures myocardial unipolar voltage and linear local shortening. In theory a matched decrease indicates scar tissue, whereas reduced linear local shortening with normal unipolar voltage indicates tissue hibernation. The main advantage of this system is its ability to assess myocardial viability online, thus allowing the intervention cardiologist to proceed with treatment in the same session. Few studies have been conducted on the diagnostic accuracy of the NOGA system and their results vary. We compared NOGA and PET measurements in patients suffering from severe coronary artery disease. In this patient group we could not reproduce the sensitivity and specificity levels reported in earlier studies. This may in part be explained by the diffuse and extensive nature of coronary artery disease in the study group. However, the advantage of having an online assessment tool remains evident.
Study aim - to elucidate possibilities of the use of precision administration of mononuclear bone marrow cells (MBMC) for the treatment of myocardial ischemia and heart failure. "Intramyocardial ...Multiple Precision Administration of Mononuclear Bone Marrow Cells in the Treatment of Myocardial Ischemia" was a double blind randomized placebo controlled study in which we included patients more or equal 6 months after Q-wave myocardial infarction with systolic myocardial dysfunction (ejection fraction <35%), not requiring myocardial revascularization, receiving stable optimal medical therapy for more or equal 8 weeks, and with implanted cardioverter-defibrillator. Transplantation of MBMC was guided by fluoroscopy and tridimensional NOGA XP Cardiac Navigation System. For assessment of efficacy of the method we used surrogate end points: decrease of number of fixed perfusion defects according to SPECT data and improvement of regional myocardial contractility according to data of echocardiography. Results of dynamic observation of the first experience of MBMC administration are presented in this paper.
Autologous skeletal myoblast transplantation (ASMT) for myocardial regeneration is a promising new treatment for patients with congestive heart failure secondary to myocardial infarction (MI). ...However, non-surgical delivery could broaden the utility of this approach. The present study was designed to evaluate the safety and feasibility of transplanting autologous skeletal myoblast (ASM) via endovascular delivery into the infarcted swine myocardium.
Seven female Yorkshire swine successfully underwent induced left ventricular MI. ASM biopsies were obtained from the hind limb of each animal and myoblasts were expanded in vitro. In a pilot experiment, ASM were labeled with iridium and short-term retention and biodistribution was determined 2 h after ASM delivery via the MyoStar™ needle-injection catheter inserted through the femoral artery. At 30 days post-infarction, the remaining animals were divided into three groups containing 2 animals each for percutaneous catheter delivery into the infarcted zone: group 1 control animals were injected with media only, group 2 and 3 animals were injected with approximately 300
×
10
6 and 600
×
10
6 ASM, respectively. Sixty days post-transplantation, the swine hearts were harvested.
During the 60-day period between transplantation and harvest, no adverse events were recorded, and continuous rhythm monitoring revealed no arrhythmias. In the small sampling size, myocardial function assessments revealed a trend toward improvement in the treatment groups with respect to ejection fraction, viability, and cardiac index. However, histology of treated swine hearts identified no skeletal muscle cells.
Percutaneous ASMT into an infarcted swine myocardium is feasible and safe, and may contribute to overall improved heart function.
Članek opisuje zdravstveno nego bolnika z akutno ishemijo spodnjih okončin. V članku je opisana akutna ishemija spodnje okončine z medicinskega vidika, kjer so predstavljeni vzroki, klinična slika, ...zdravljenje in zapleti. Zdravstvena nega pa zajema posebnosti sprejema bolnika na Klinični oddelek za kirurgijo srca in ožilja Kliničnega centra v Ljubljani, pripravo bolnika na operacijo, postoperativno zdravstveno nego in zdravstveno vzgojo bolnika. Zdravstvena nega bolnika z akutno ishemijo spodnje okončine poteka po procesni metodi dela, postavljene so negovalne diagnoze, cilji, postopki in posegi zdravstvene nege. Proces zdravstvene nege je zaključen z vrednotenjem zdravstvene nege.
