The upright posture of man had been a major evolutional challenge. The mechanisms responsible for orthostatic tolerance mostly affect the venous system. In this paper, we discuss new results regarding the biomechanics of the venous system highlighting a rather neglected field, the biomechanical properties of the vein wall. These properties change according to localization of veins, age, gender and body mass. The anti-gravitational adaptation of veins is a complex process involving all three layers of the venous wall. Local myogenic and humoral mechanisms as well as systemic hormonal and nervous influences control the adaptive processes in the veins. Long term adaptation involves structural and functional remodeling of the venous wall. Disorders of the veins mostly cause pathological remodeling. Hemodynamic factors (pressure and flow) together with inflammatory processes may lead to pathological alterations, changing the biomechanical properties of the vein wall, which further contribute to the reservation and progression of venous dysfunction. Appropriate testing of venous function can reveal biomechanical disorders even in clinically asymptomatic patients. Thus, biomechanical investigation of veins not only helps to understand the underlying pathomechanism but it also can contribute to early diagnosis and follow-up of venous disorders. When recognized in time, pathological remodeling can be prevented or treated. In this way, the incidence of venous disorder could be cut back reducing both human suffering and material loss.
Aortic valve stenosis is one of the most prevalent valvular disease with significant clinical burden. While it is initially a disorder of the left ventricle (LV), long-term effects of the disease also affect the right ventricle (RV) as well. Nevertheless, data are scarce regarding the changes of RV mechanics and their association with symptomatic status of the patients. 3D echocardiography allows a more detailed assessment of the RV, which may unveil distinct changes of its morphology and function in this clinical setting. Accordingly, our aim was to examine LV and RV mechanics in TAVR candidate patients with severe aortic stenosis using three-dimensional (3D) echocardiography. Seventy patients (51% male, age: 80±6 years) were enrolled. Detailed medical history and symptomatic status were obtained. Beyond conventional transthoracic echocardiographic protocol, 3D loops were also acquired. We measured 3D LV and RV end-diastolic volume indexed to body surface area (EDVi), ejection fraction (EF) and global longitudinal (GLS) using dedicated software. Furthermore, we have determined 3D RV global longitudinal (RV GLS) and circumferential strain (RV GCS) using the ReVISION method. LV EF (r=0.28, p<0.05) and LV GLS (r=−0.26, p<0.05) significantly correlated with age, while RV EF (r=0.21, p=0.11), RV GLS (r=−0.17, p=0.19) and RV GCS (r=−0.07, p=0.61) did not show association with it. 41% (n=29) of the patient population mentioned angina or had syncope. Patients with these symptoms had comparable LV EDVi (73±23 vs. 69±25 mL/m2, p=0.47), LV EF (47±15 vs. 51±10%, p=0.14) and LV GLS (−13.6±4.8 vs. −14.8±2.6%, p=0.25) to those who did not mention these complaints. On the other hand, patients with angina or syncope in their medical history had significantly lower RV EDVi (58±13 vs. 70±23 mL/m2, p<0.05), while having significantly higher RV EF (46±10 vs. 52±7%, p<0.05). Moreover, symptomatic patients had significantly lower RV GCS (−15.7±5.6 vs. −19.6±5.3%, p<0.01), while RV GLS did not differ (−15.8±4.8 vs. −17.4±4.1%, p=0.17). Patients with severe aortic stenosis have marked changes in not only the LV, but the RV mechanics as well. While the symptomatic status does not seem to be associated with LV morphology and function, patients with angina or syncope had distinct changes in RV size and the contraction pattern of the chamber. Funding Acknowledgement Type of funding sources: None.
Az aorta-bal kamra tunnel egy ritka veleszületett szívfejlődési rendellenesség, az aortabillentyűt megkerülő kóros kapcsolat az aorta és a bal kamra között. A szerzők egy 14 éves fi ú esetét ismertetik, akinél a jobb Valsalva-tasakban, az eredésénél pericardiumfolttal zárták a tunnelt. A kétdimenziós echokardiográfi ás anatómiai diagnózist háromdi-menzios vizsgálattal egészítették ki és mágneses rezonanciavizsgálattal erősítették meg. Esetük az első az irodalomban, amelynél a fenti komplex diagnosztikát alkalmazták a pre-és posztoperatív kezelés során. Az újonnan alkalmazott transthoracalis háromdimenziós módszerrel optimalizálható az aorta-bal kamra tunnel anatómiai és hemodinamikai diagnosztikája és posztoperatív utánkövetése. Orv. Hetil., 2015, 156(28), 1140-1143.Kulcsszavak: aorta-bal kamra tunnel, 3D echokardiográfi a Successful surgical management of aortico-left ventricular tunnel using modern noninvasive diagnostic imaging methodsAortico-left ventricular tunnel is a rare congenital cardiac defect, which bypasses the aortic valve via the paravalvar connection from the aorta to the left ventricle. The authors report the history of a 14-year-old boy with aortico-left ventricular tunnel in whom the aortic orifi ce arose from the right aortic sinus and was closed by a pericardial patch. The diagnosis was confi rmed by combined two-dimensional and real time three-dimensional echocardiogram and magnetic resonance imaging. This is the fi rst case, in which these complex diagnostic imaging methods have been used in the pre-and postoperative management of this defect. Optimally the new transthoratic three-dimensional echocardiography would be needed to defi ne the anatomy and functional consequences of the aortico-left ventricular tunnel and in the postoperative follow-up. Keywords: aortico-left ventricular tunnel, real time three-dimensional echocardiogramHartyánszky, I., Katona, M., Kádár, K., Apor, A., Varga, S., Simon, J., Tóth, A., Karácsony, T., Bogáts, G. [Successful surgical management of aortico-left ventricular tunnel using modern noninvasive diagnostic imaging methods]. Orv. Hetil., 2015, 156(28), 1140-1143. ESETISMERTETÉS RövidítésekAo = aorta; BKD = balkamra-diasztolé; BKF = balkamra-fal; Bp = bal pitvar; CT = komputertomográfi a; 3D = háromdi-menziós; 3DE = háromdimenziós echokardiográfi a; IVS = interventricularis septum; lin. EF = lineáris ejekciós frakció; MR = mágneses rezonancia; TEE = transoesophagealis echokardiográfi a
Funding Acknowledgements Type of funding sources: None. Patients with left bundle branch block (LBBB) are known to have substantially increased afterload sensitivity. It gains particular importance in subjects with aortic stenosis: patients with pre-existing LBBB may benefit more from interventions such as transcatheter aortic valve replacement (TAVR) by an effective and rapid reduction of the left ventricular (LV) pressures. Accordingly, our aim was to investigate the changes of LV myocardial work indices in patients undergoing TAVR by the presence of preoperative LBBB. Non-invasive myocardial work indices are novel echocardiographic parameters which adjust LV deformation to the instantaneous LV pressure, overcoming the the load-sensitivity of the traditional LV functional measures. Thirty patients undergoing TAVR were enrolled (37% female; age: 78±6 years; aortic valve area [AVA]: 0.7±0.3 cm2). Fourteen patients (47%; LBBB group) showed LBBB pattern on ECG, by demonstrating native LBBB (n=6; 20%) or having ventricular pacing dependency (n=8; 27%), while 16 patients had narrow QRS (53%; non-LBBB group). Prior to the procedure, subjects underwent a detailed echocardiographic investigation. Speckle-tracking analysis was performed and global longitudinal strain (GLS) was measured. LV pressure curve was estimated by adding the mean aortic valve gradient to the aortic systolic pressure. Using these measures, LV global constructive work index (CMWI) and global work efficiency (GWE). were quantified by commercially available software. A 6 months follow-up examination was also performed and at that time point we determined the aforementioned parameters. As expected, AVA significantly improved after the procedure in the pooled study group (1.8±0.4 cm2; p<0.001). GLS also significantly increased (-13.2±4.2 vs. -15.2±3.9 %; p<0.01), while CMWI only showed a tendential decrease (2422±788 vs. 2166±640 mmHg%; p=NS) at the follow-up. GLS (-10.6±3.7 vs. -15.5±3.4%; p<0.001), CMWI (1877±679 vs. 2898±529 mmHg%; p<0.001), and also GWE (82±9 vs. 91±4%; p<0.01) was significantly lower in the LBBB-group compared to the non-LBBB patients. At the follow-up, GLS was still significantly lower in the LBBB patients (-13.2±4.6 vs. -16.9±2.1%; p<0.01), however, CMWI was comparable between the two groups (1956±776 vs. 2350±439 mmHg%, p=NS). Pressure overload of the LV may affect patients with LBBB substantially more than subjects without it. TAVR causes an immediate and significant decrease in the LV afterload, which results in a more pronounced improvement in the LBBB group compared to those with no LBBB.
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