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2.
J Cardiothorac Vasc Anesth ; 31(1): 134-141, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27590457

RESUMEN

OBJECTIVE: To evaluate the effect of acute cardiac sympathectomy by thoracic epidural anesthesia on myocardial blood flow and microvascular function. DESIGN: A prospective observational study. SETTING: The study was conducted in a tertiary teaching hospital. PARTICIPANTS: Ten patients with a mean age of 48 years (range 22-63 years) scheduled for thoracic surgery. INTERVENTIONS: Myocardial contrast echocardiography was used to study myocardial blood flow and microvascular responsiveness at rest, during adenosine-induced hyperemia, and after sympathetic stimulation by the cold pressor test. Repeated measurements were performed without and with thoracic epidural anesthesia. MEASUREMENTS AND MAIN RESULTS: An increased myocardial blood volume was observed with thoracic epidural anesthesia compared to baseline (from 0.08±0.02 to 0.10±0.03 mL/mL; p = 0.02). No difference existed in resting myocardial blood flow between baseline conditions and epidural anesthesia (0.85±0.24 v 1.03±0.27 mL/min/g, respectively). Hyperemia during thoracic epidural anesthesia increased myocardial blood flow to 4.31±1.07 mL/min/g (p = 0.0008 v baseline) and blood volume to 0.17±0.04 mL/mL (p = 0.005 baseline). After sympathetic stimulation, no difference in myocardial blood flow parameters was observed CONCLUSIONS: Acute cardiac sympathectomy by thoracic epidural anesthesia increased the blood volume in the myocardial capillary system. Also, thoracic epidural anesthesia increased hyperemic myocardial blood flow, indicating augmented endothelial-independent vasodilator capacity of the myocardium.


Asunto(s)
Anestesia Epidural/métodos , Vasos Coronarios/fisiopatología , Simpatectomía/métodos , Adulto , Bloqueo Nervioso Autónomo/métodos , Circulación Coronaria/fisiología , Vasos Coronarios/diagnóstico por imagen , Ecocardiografía , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Microcirculación/fisiología , Persona de Mediana Edad , Estudios Prospectivos , Vértebras Torácicas , Vasodilatación/fisiología , Adulto Joven
3.
J Electrocardiol ; 49(4): 496-503, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27016257

RESUMEN

PURPOSE: Paroxysmal atrial fibrillation (PAF) often remains undiagnosed. Long-term surface ECG is used for screening, but has limitations. Esophageal ECG (eECG) allows recording high quality atrial signals, which were used to identify markers for PAF. METHODS: In 50 patients (25 patients with PAF; 25 controls) an eECG and surface ECG was recorded simultaneously. Partially A-V blocked atrial runs (PBARs) were quantified, atrial signal duration in eECG was measured. RESULTS: eECG revealed 1.8‰ of atrial premature beats in patients with known PAF to be PBARs with a median duration of 853ms (interquartile range (IQR) 813-1836ms) and a median atrial cycle length of 366ms (IQR 282-432ms). Even during a short recording duration of 2.1h (IQR 1.2-17.2h), PBARs occurred in 20% of PAF patients but not in controls (p=0.05). Left atrial signal duration was predictive for PAF (72% sensitivity, 80% specificity). CONCLUSIONS: eECG reveals partially blocked atrial runs and prolonged left atrial signal duration - two novel surrogate markers for PAF.


Asunto(s)
Enfermedades Asintomáticas , Fibrilación Atrial/diagnóstico , Diagnóstico por Computador/métodos , Electrocardiografía/métodos , Anciano , Algoritmos , Biomarcadores , Esófago , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
4.
Ther Umsch ; 72(8): 529-35, 2015 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-26227982

RESUMEN

Cardiac pacemakers are routinely used for the treatment of bradyarrhythmias. Contemporary pacemakers are reliable and allow for a patient specific programming. However, pacemaker replacements due to battery depletion are common (~25 % of all implantation procedures) and bear the risk of complications. Batteryless pacemakers may allow overcoming this limitation. To power a batteryless pacemaker, a mechanism for intracorporeal energy harvesting is required. Such a generator may consist out of subcutaneously implanted solar cells, transforming the small amount of transcutaneously available light into electrical energy. Alternatively, intravascular turbines may harvest energy from the blood flow. Energy may also be harvested from the ventricular wall motion by a dedicated mechanical clockwork converting motion into electrical energy. All these approaches have successfully been tested in vivo. Pacemaker leads constitute another Achilles heel of contemporary pacemakers. Thus, leadless devices are desired. Miniaturized pacemaker circuits and suitable energy harvesting mechanisms (incorporated in a single device) may allow catheter-based implantation of the pacemaker in the heart. Such miniaturized battery- and leadless pacemakers would combine the advantages of both approaches and overcome major limitations of today's systems.


Asunto(s)
Bradicardia/terapia , Marcapaso Artificial/tendencias , Diseño de Prótesis/tendencias , Suministros de Energía Eléctrica/tendencias , Electrodos Implantados , Predicción , Humanos , Suiza
5.
Europace ; 16(10): 1534-9, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24916431

RESUMEN

AIMS: Today's cardiac pacemakers are powered by batteries with limited energy capacity. As the battery's lifetime ends, the pacemaker needs to be replaced. This surgical re-intervention is costly and bears the risk of complications. Thus, a pacemaker without primary batteries is desirable. The goal of this study was to test whether transcutaneous solar light could power a pacemaker. METHODS AND RESULTS: We used a three-step approach to investigate the feasibility of sunlight-powered cardiac pacing. First, the harvestable power was estimated. Theoretically, a subcutaneously implanted 1 cm(2) solar module may harvest ∼2500 µW from sunlight (3 mm implantation depth). Secondly, ex vivo measurements were performed with solar cells placed under pig skin flaps exposed to a solar simulator and real sunlight. Ex vivo measurements under real sunlight resulted in a median output power of 4941 µW/cm(2) [interquartile range (IQR) 3767-5598 µW/cm(2), median skin flap thickness 3.0 mm (IQR 2.7-3.3 mm)]. The output power strongly depended on implantation depth (ρSpearman = -0.86, P < 0.001). Finally, a batteryless single-chamber pacemaker powered by a 3.24 cm(2) solar module was implanted in vivo in a pig to measure output power and to pace. In vivo measurements showed a median output power of >3500 µW/cm(2) (skin flap thickness 2.8-3.84 mm). Successful batteryless VVI pacing using a subcutaneously implanted solar module was performed. CONCLUSION: Based on our results, we estimate that a few minutes of direct sunlight (irradiating an implanted solar module) allow powering a pacemaker for 24 h using a suitable energy storage. Thus, powering a pacemaker by sunlight is feasible and may be an alternative energy supply for tomorrow's pacemakers.


Asunto(s)
Suministros de Energía Eléctrica , Marcapaso Artificial , Luz Solar , Animales , Diseño de Equipo , Estudios de Factibilidad , Ensayo de Materiales , Porcinos
6.
Artif Organs ; 38(5): E68-81, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24646095

RESUMEN

Replacement intervals of implantable medical devices are commonly dictated by battery life. Therefore, intracorporeal energy harvesting has the potential to reduce the number of surgical interventions by extending the life cycle of active devices. Given the accumulated experience with intravascular devices such as stents, heart valves, and cardiac assist devices, the idea to harvest a small fraction of the hydraulic energy available in the cardiovascular circulation is revisited. The aim of this article is to explore the technical feasibility of harvesting 1 mW electric power using a miniature hydrodynamic turbine powered by about 1% of the cardiac output flow in a peripheral artery. To this end, numerical modelling of the fluid mechanics and experimental verification of the overall performance of a 1:1 scale friction turbine are performed in vitro. The numerical flow model is validated for a range of turbine configurations and flow conditions (up to 250 mL/min) in terms of hydromechanic efficiency; up to 15% could be achieved with the nonoptimized configurations of the study. Although this article does not entail the clinical feasibility of intravascular turbines in terms of hemocompatibility and impact on the circulatory system, the numerical model does provide first estimates of the mechanical shear forces relevant to blood trauma and platelet activation. It is concluded that the time-integrated shear stress exposure is significantly lower than in cardiac assist devices due to lower flow velocities and predominantly laminar flow.


Asunto(s)
Suministros de Energía Eléctrica , Corazón Auxiliar , Gasto Cardíaco , Simulación por Computador , Diseño de Equipo , Humanos , Hidrodinámica , Miniaturización , Modelos Cardiovasculares
7.
J Electrocardiol ; 47(1): 29-37, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24238737

RESUMEN

BACKGROUND: Ischemia monitoring cannot always be performed by 12-lead ECG. Hence, the individual performance of the ECG leads is crucial. No experimental data on the ECG's specificity for transient ischemia exist. METHODS: In 45 patients a 19-lead ECG was registered during a 1-minute balloon occlusion of a coronary artery (left anterior descending artery [LAD], right coronary artery [RCA] or left circumflex artery [LCX]). ST-segment shifts and sensitivity/specificity of the leads were measured. RESULTS: During LAD occlusion, V3 showed maximal ST-segment elevation (0.26mV [IQR 0.16-0.33mV], p=0.001) and sensitivity/specificity (88% and 80%). During RCA occlusion, III showed maximal ST-elevation (0.2mV [IQR 0.09-0.26mV], p=0.004), aVF had the best sensitivity/specificity (85% and 68%). During LCX occlusion, V6 showed maximal ST-segment elevation (0.04mV [IQR 0.02-0.14mV], p=0.005), and sensitivity/specificity was (31%/92%) but could be improved (63%/72%) using an optimized cut-off for ischemia. CONCLUSION: V3, aVF and V6 show the best performance to detect transient ischemia.


Asunto(s)
Algoritmos , Oclusión Coronaria/complicaciones , Oclusión Coronaria/diagnóstico , Diagnóstico por Computador/métodos , Electrocardiografía/métodos , Anciano , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Anesth Analg ; 116(4): 767-74, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23385053

RESUMEN

BACKGROUND: Preservation of myocardial perfusion during general anesthesia is likely important in patients at risk for perioperative cardiac complications. Data related to the influence of general anesthesia on the normal myocardial circulation are limited. In this study, we investigated myocardial microcirculatory responses to pharmacological vasodilation and sympathetic stimulation during general anesthesia with sevoflurane in healthy humans immediately before surgical stimulation. METHODS: Six female and 7 male subjects (mean age 43 years, range 28-61) were studied at baseline while awake and during the administration of 1 minimum alveolar concentration sevoflurane. Using myocardial contrast echocardiography, myocardial blood flow (MBF) and microcirculatory variables were assessed at rest, during adenosine-induced hyperemia, and after cold pressor test-induced sympathetic stimulation. MBF was calculated from the relative myocardial blood volume multiplied by its exchange frequency (ß) divided by myocardial tissue density (ρT), which was set at 1.05 g·mL(-1). RESULTS: During sevoflurane anesthesia, MBF at rest was similar to baseline values (1.05 ± 0.28 vs 1.05 ± 0.32 mL·min(-1)·g(-1); P = 0.98; 95% confidence interval [CI], -0.18 to 0.18). Myocardial blood volume decreased (P = 0.0044; 95% CI, 0.01-0.04) while its exchange frequency (ß) increased under sevoflurane anesthesia when compared with baseline. In contrast, hyperemic MBF was reduced during anesthesia compared with baseline (2.25 ± 0.5 vs 3.53 ± 0.7 mL·min(-1)·g(-1); P = 0.0003; 95% CI, 0.72-1.84). Sympathetic stimulation during sevoflurane anesthesia resulted in a similar MBF compared to baseline (1.53 ± 0.53 and 1.55 ± 0.49 mL·min(-1)·g(-1); P = 0.74; 95% CI, -0.47 to 0.35). CONCLUSIONS: In otherwise healthy subjects who are not subjected to surgical stimulation, MBF at rest and after sympathetic stimulation is preserved during sevoflurane anesthesia despite a decrease in myocardial blood volume. However, sevoflurane anesthesia reduces hyperemic MBF, and thus MBF reserve, in these subjects.


Asunto(s)
Anestesia General , Anestésicos por Inhalación , Volumen Sanguíneo/efectos de los fármacos , Circulación Coronaria/efectos de los fármacos , Corazón/efectos de los fármacos , Hiperemia/fisiopatología , Éteres Metílicos , Adulto , Algoritmos , Catecolaminas/sangre , Frío , Interpretación Estadística de Datos , Ecocardiografía/métodos , Femenino , Humanos , Masculino , Microcirculación/efectos de los fármacos , Persona de Mediana Edad , Músculo Liso Vascular/efectos de los fármacos , Presión , Sevoflurano , Vasodilatación/efectos de los fármacos
9.
J Electrocardiol ; 46(2): 158-65, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23305907

RESUMEN

BACKGROUND: Diagnosing supraventricular arrhythmias by conventional long-term ECG can be cumbersome because of poor p-waves. Esophageal long-term electrocardiography (eECG) has an excellent sensitivity for atrial signals and may overcome this limitation. However, the optimal lead insertion depth (OLID) is not known. METHODS: We registered eECGs at different lead insertion depths in 27 patients and analyzed 199,716 atrial complexes with respect to signal amplitude and slope. Correlation and regression analyses were used to find a criterion for OLID. RESULTS: Atrial signal amplitudes and slopes significantly depend on lead insertion depth. OLID correlates with body height (rSpearman=0.71) and can be estimated by OLID [cm]=0.25*body height[cm]-7cm. At this insertion depth, we recorded the largest esophageal atrial signal amplitudes (1.27±0.86mV), which were much larger compared to conventional surface lead II (0.19±0.10mV, p<0.0001). CONCLUSION: The OLID depends on body height and can be calculated by a simple regression formula.


Asunto(s)
Fibrilación Atrial/diagnóstico , Electrocardiografía/instrumentación , Electrocardiografía/métodos , Electrodos Implantados , Esófago/cirugía , Adulto , Femenino , Humanos , Masculino , Implantación de Prótesis/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
10.
Eur Heart J ; 33(11): 1334-43, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22285579

RESUMEN

AIMS: Late acquired incomplete stent apposition (ISA) is more common after drug-eluting stent (DES) than bare metal stent (BMS) implantation and has been associated with vascular hypersensitivity and stent thrombosis (ST). We investigated the impact of incidentally discovered ISA as assessed by intravascular ultrasound (IVUS) 8 months after DES implantation on the long-term clinical outcome. METHODS AND RESULTS: A total of 194 patients with 221 lesions were prospectively followed through 5 years. At 8 months, IVUS showed evidence of ISA among 37 patients with 39 lesions (18%) (mean ISA(max) 4.7 ± 5.0 mm(2)), whereas no ISA was observed among 157 patients with 182 lesions. Incomplete stent apposition was more prevalent among segments treated with sirolimus-eluting (n = 103) than paclitaxel-eluting stents (n = 118) (27 vs. 9%, P = 0.001). Between IVUS investigation at the 8-month and 5-year follow-up, major adverse cardiac events occurred more frequently in patients with (18.9%, n = 7) than without ISA (7.0%, n = 11) (HR = 2.71, 95% CI: 1.05-6.96, P = 0.031). While there were no differences with respect to death, the rate of myocardial infarction was higher among patients with (13.5%, n = 5) than without ISA (1.9%, n = 3) (HR = 7.53, 95% CI: 1.79-31.6, P = 0.001). Very late ST was more common among patients with than without ISA [Academic Research Consortium-definite ST:13.5% (n = 5) vs. 0.6% (n = 1) HR = 23.2, 95% CI: 2.65-203, P < 0.001]. CONCLUSION: In the present study, the presence of ISA as assessed by IVUS 8 months after DES implantation was associated with a higher rate of myocardial infarction and very late stent thrombosis during long-term follow-up. The prognostic impact of ISA on long-term clinical outcomes requires further investigation.


Asunto(s)
Prótesis Vascular , Stents Liberadores de Fármacos/efectos adversos , Isquemia Miocárdica/terapia , Falla de Prótesis , Anciano , Femenino , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico por imagen , Oclusión de Injerto Vascular/etiología , Humanos , Inmunosupresores/administración & dosificación , Hallazgos Incidentales , Masculino , Persona de Mediana Edad , Paclitaxel/administración & dosificación , Estudios Prospectivos , Método Simple Ciego , Sirolimus/administración & dosificación , Resultado del Tratamiento , Moduladores de Tubulina/administración & dosificación , Ultrasonografía Intervencional
11.
Circulation ; 123(24): 2819-28, 6 p following 2828, 2011 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-21646500

RESUMEN

BACKGROUND: Long-term comparative data of first-generation drug-eluting stents are scarce. We investigated clinical and angiographic outcomes of sirolimus-eluting (SES) and paclitaxel-eluting stents (PES) at 5 years as part of the Sirolimus-Eluting Versus Paclitaxel-Eluting Stents for Coronary Revascularization (SIRTAX) LATE study. METHODS AND RESULTS: A total of 1012 patients were randomly assigned to SES or PES. Repeat angiography was completed in 444 of 1012 patients (43.8%) at 5 years. Major adverse cardiac events occurred in 19.7% of SES- and 21.4% of PES-treated patients (hazard ratio, 0.89; 95% confidence interval, 0.68 to 1.17; P=0.39) at 5 years. There were no differences between SES and PES in terms of cardiac death (5.8% versus 5.7%; P=0.35), myocardial infarction (6.6% versus 6.9%; P=0.51), and target lesion revascularization (13.1% versus 15.1%; P=0.29). Between 1 and 5 years, the annual rate of target lesion revascularization was 2.0% (95% confidence interval, 1.4% to 2.6%) for SES and 1.4% (95% confidence interval, 0.9% to 2.0%) for PES. Among patients undergoing paired angiography at 8 months and 5 years, delayed lumen loss amounted to 0.37 ± 0.73 mm for SES and 0.29 ± 0.59 mm for PES (P=0.32). The overall rate of definite stent thrombosis was 4.6% for SES and 4.1% for PES (P=0.74), and very late definite stent thrombosis occurred at an annual rate of 0.65% (95% confidence interval, 0.40% to 0.90%). CONCLUSIONS: Long-term follow-up of first-generation drug-eluting stents shows no significant differences in clinical and angiographic outcomes between SES and PES. The continuous increase in late lumen loss in conjunction with the ongoing risk of very late stent thrombosis suggests that vascular healing remains incomplete up to 5 years after implantation of first-generation drug-eluting stents.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Enfermedad de la Arteria Coronaria/terapia , Stents Liberadores de Fármacos , Paclitaxel/uso terapéutico , Sirolimus/uso terapéutico , Anciano , Antineoplásicos Fitogénicos/uso terapéutico , Trombosis Coronaria/prevención & control , Femenino , Estudios de Seguimiento , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
13.
Catheter Cardiovasc Interv ; 79(2): 263-70, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22131255

RESUMEN

BACKGROUND: Iatrogenic free wall cardiac perforation is a rare but serious complication encountered during percutaneous cardiac procedures, which usually leads to tamponade and death. Septal occluder devices have been developed for sealing intracardiac shunts but may be also used in this emergency setting. METHODS AND RESULTS: We report a small series of five consecutive cases of iatrogenic heart perforations that were treated with implantation of Amplatzer Septal Occluders (ASO). In the first case, iatrogenic left ventricle (LV) perforation occurred during LV biopsy and could be closed up with a 4 mm ASO. In the second case, a 4 mm ASO was used for sealing of a right atrial perforation allocated to Port-a-Cath dislodgment. The third case happened during transseptal puncture for implantation of a TandemHeart bVAD device in a patient suffering cardiogenic shock and was treated by implantation of a 5 mm ASO. The fourth patient was transferred to our facilities for percutaneous closure of an acute post-infarct VSD after anteroseptal myocardial infarction. This procedure was complicated by perforation of the posterolateral free wall and led to the deployment of 12 mm ASO. The last patient suffered from free LV wall perforation during investigation of a severe aortic stenosis and was treated by implantation of 4 mm ASO. All patients were alive after 24 hrs but the last patient died during the in-hospital stay of a right ventricular infarction complicated by multiple organ failure. CONCLUSIONS: Percutaneous device occlusion of iatrogenic heart perforation seems to be a safe and efficient method to treat iatrogenic heart perforation. In order to perform this elegant method, it is however imperative not to prematurely withdraw the perforating catheter to maintain access to the hole for closure.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos/efectos adversos , Lesiones Cardíacas/cirugía , Ventrículos Cardíacos/lesiones , Implantación de Prótesis/métodos , Dispositivo Oclusor Septal , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Lesiones Cardíacas/etiología , Humanos , Complicaciones Intraoperatorias , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
14.
Anesth Analg ; 114(5): 938-45, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22366851

RESUMEN

Ultrasound contrast agents are gas-filled microbubbles that enhance visualization of cardiac structures, function and blood flow during contrast-enhanced ultrasound (CEUS). An interesting cardiovascular application of CEUS is myocardial contrast echocardiography, which allows real-time myocardial perfusion imaging. The intraoperative use of this technically challenging imaging method is limited at present, although several studies have examined its clinical utility during cardiac surgery in the past. In the present review we provide general information on the basic principles of CEUS and discuss the methodology and technical aspects of myocardial perfusion imaging.


Asunto(s)
Medios de Contraste , Circulación Coronaria/fisiología , Ecocardiografía/métodos , Microburbujas , Estimulación Acústica , Sistemas de Computación , Corazón/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Monitoreo Intraoperatorio/métodos , Tamaño de la Partícula , Perfusión , Periodo Perioperatorio , Reproducibilidad de los Resultados , Cirugía Torácica/instrumentación , Cirugía Torácica/métodos
15.
Cardiovasc Eng Technol ; 13(2): 207-218, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34409579

RESUMEN

PURPOSE: The pre-clinical testing of cardiovascular implants gains increasing attention due to the complexity of novel implants and new medical device regulations. It often relies on large animal experiments that are afflicted with ethical and methodical challenges. Thus, a method for simulating physiological heart motions is desired but lacking so far. METHODS: We developed a robotic platform that allows simulating the trajectory of any point of the heart (one at a time) in six degrees of freedom. It uses heart motion trajectories acquired from cardiac magnetic resonance imaging or accelero-meter data. The rotations of the six motors are calculated based on the input trajectory. A closed-loop controller drives the platform and a graphical user interface monitors the functioning and accuracy of the robot using encoder data. RESULTS: The robotic platform can mimic physiological heart motions from large animals and humans. It offers a spherical work envelope with a radius of 29 mm, maximum acceleration of 20 m/s2 and maximum deflection of ±19° along all axes. The absolute mean positioning error in x-, y- and z-direction is 0.21 ±0.06, 0.31 ±0.11 and 0.17 ±0.12 mm, respectively. The absolute mean orientation error around x-, y- and z-axis (roll, pitch and yaw) is 0.24 ±0.18°, 0.23 ±0.13° and 0.18 ±0.18°, respectively. CONCLUSION: The novel robotic approach allows reproducing heart motions with high accuracy and repeatability. This may benefit the device development process and allows re-using previously acquired heart motion data repeatedly, thus avoiding animal trials.


Asunto(s)
Desfibriladores Implantables , Robótica , Animales , Robótica/métodos
16.
Am J Physiol Heart Circ Physiol ; 300(3): H1119-24, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21217067

RESUMEN

Animal experiments have shown that the coronary circulation is pressure distensible, i.e., myocardial blood volume (MBV) increases with perfusion pressure. In humans, however, corresponding measurements are lacking so far. We sought to quantify parameters reflecting coronary distensibility such as MBV and coronary resistance (CR) during and after coronary angioplasty. Thirty patients with stable coronary artery disease underwent simultaneous coronary perfusion pressure assessment and myocardial contrast echocardiography (MCE) of 37 coronary arteries and their territories during and after angioplasty. MCE yielded MBV and myocardial blood flow (MBF; in ml · min(-1) · g(-1)). Complete data sets were obtained in 32 coronary arteries and their territories from 26 patients. During angioplasty, perfusion pressure, i.e., coronary occlusive pressure, and MBV varied between 9 and 57 mmHg (26.9 ± 11.9 mmHg) and between 1.2 and 14.5 ml/100 g (6.7 ± 3.7 ml/100 g), respectively. After successful angioplasty, perfusion pressure and MBV increased significantly (P < 0.001 for both) and varied between 64 and 118 mmHg (93.5 ± 12.8 mmHg) and between 3.7 and 17.3 ml/100 g (9.8 ± 3.4 ml/100 g), respectively. Mean MBF increased from 31 ± 20 ml · min(-1) · g(-1) during coronary occlusion, reflecting collateral flow, to 121 ± 33 ml · min(-1) · g(-1) (P < 0.01), whereas mean CR, i.e., the ratio of perfusion pressure and MBF, decreased by 20% (P < 0.001). In conclusion, the human coronary circulation is pressure distensible. MCE allows for the quantification of CR and MBV in humans.


Asunto(s)
Angioplastia Coronaria con Balón/métodos , Circulación Coronaria/fisiología , Miocardio/patología , Anciano , Volumen Sanguíneo/fisiología , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Enfermedad de la Arteria Coronaria/terapia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Ecocardiografía/métodos , Corazón/fisiopatología , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad
17.
Catheter Cardiovasc Interv ; 77(1): 5-12, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-20506333

RESUMEN

OBJECTIVES: We aimed at comparing the long term clinical outcome of SES and PES in routine clinical practice. BACKGROUND: Although sirolimus-eluting stents (SES) more effectively reduce neointimal hyperplasia than paclitaxel-eluting stents (PES), uncertainty prevails whether this difference translates into differences in clinical outcomes outside randomized controlled trials with selected patient populations and protocol-mandated angiographic follow-up. METHODS: Nine hundred and four consecutive patients who underwent implantation of a drug-eluting stent between May 2004 and February 2005: 467 patients with 646 lesions received SES, 437 patients with 600 lesions received PES. Clinical follow-up was obtained at 2 years without intervening routine angiographic follow-up. The primary endpoint was a composite of death, myocardial infarction (MI), or target vessel revascularization (TVR). RESULTS: At 2 years, the primary endpoint was less frequent with SES (12.9%) than PES (17.6%, HR = 0.70, 95% CI 0.50-0.98, P = 0.04). The difference in favor of SES was largely driven by a lower rate of target lesion revascularisation (TLR; 4.1% vs. 6.9%, P = 0.05), whereas rates of death (6.4% vs. 7.6%, P = 0.49), MI (1.9% vs. 3.2%, P = 0.21), or definite stent thrombosis (0.6% vs. 1.4%, P = 0.27) were similar for both stent types. The benefit regarding reduced rates of TLR was significant in nondiabetic (3.6% vs. 7.1%, P = 0.04) but not in diabetic patients (5.6% vs. 6.1%, P = 0.80). CONCLUSIONS: SES more effectively reduced the need for repeat revascularization procedures than PES when used in routine clinical practice. The beneficial effect is maintained up to 2 years and may be less pronounced in diabetic patients.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Fármacos Cardiovasculares/administración & dosificación , Estenosis Coronaria/terapia , Stents Liberadores de Fármacos , Paclitaxel/administración & dosificación , Sirolimus/administración & dosificación , Anciano , Angioplastia Coronaria con Balón/efectos adversos , Angioplastia Coronaria con Balón/mortalidad , Distribución de Chi-Cuadrado , Angiografía Coronaria , Estenosis Coronaria/complicaciones , Estenosis Coronaria/diagnóstico por imagen , Diabetes Mellitus/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/etiología , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Diseño de Prótesis , Sistema de Registros , Medición de Riesgo , Factores de Riesgo , Índice de Severidad de la Enfermedad , Suiza , Trombosis/etiología , Factores de Tiempo , Resultado del Tratamiento
18.
Cardiology ; 118(3): 198-206, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21701169

RESUMEN

BACKGROUND: Coronary collaterals protect myocardium jeopardized by coronary artery disease (CAD). Promotion of collateral circulation is desirable before myocardial damage occurs. Therefore, determinants of collateral preformation in patients without CAD should be elucidated. METHODS: In 106 patients undergoing coronary angiography who were free of coronary stenoses, a total of 39 clinical test variables were collected. The coronary collateral flow index (CFI) was measured. Stepwise multiple linear regression analysis was performed after choosing a restricted number of candidates emerging from univariate testing. Separate multiple regression analyses were performed in patients with and without beta-blocker therapy. RESULTS: Nine parameters were found to be possible determinants of CFI by univariate analysis: arterial hypertension (aHT), dyslipidemia, statins, diuretics, age, height, heart rate (HR), pulse pressure amplitude, and left ventricular end-diastolic pressure (LVEDP). After multiple regression analysis, a low HR, absence of aHT, and elevated LVEDP were significantly related to CFI (F = 5.31, p = 0.002, adjusted r(2) = 0.12). In patients without beta-blockers, a low HR and absence of aHT were independent predictors of CFI (F = 8.03, p < 0.001, n = 50, adjusted r(2) = 0.30). CONCLUSIONS: A low HR and absence of aHT are both related to collateral preformation in humans. We suppose that bradycardia favors fluid shear stress in coronary arteries, thus triggering collateral growth.


Asunto(s)
Circulación Colateral/fisiología , Enfermedad de la Arteria Coronaria/fisiopatología , Circulación Coronaria/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Angiografía Coronaria , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/diagnóstico , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Factores de Riesgo , Presión Ventricular/fisiología , Adulto Joven
19.
JTCVS Open ; 8: 280-289, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36004154

RESUMEN

Objectives: This study examines the early and midterm safety, efficacy, and durability of mitral valve repair for primary mitral regurgitation (MR) using the ChordArt device (CoreMedic) for chordal replacement. Methods: Five patients with symptomatic severe primary degenerative MR due to isolated central posterior leaflet prolapse/flail were treated with the ChordArt device in a transseptal surgical approach and followed prospectively with periodical clinical and echocardiographic assessments for 2 years. Results: Reduction of MR immediately after the implantation of artificial chords was achieved in all patients showing no or trace MR (<1+/4+). In all patients, MR <1+ was maintained during 24 months of follow-up. No dehiscence, detachment, or dislocation of the implanted ChordArt devices was observed. Transthoracic echocardiography showed that left ventricle end diastolic diameter significantly decreased during the whole follow-up period in comparison to baseline condition, especially at discharge and 1-month follow-up. Left ventricle end systolic diameter also significantly decreased during the whole follow-up period in comparison to baseline condition. Left atrial volume significantly decreased during the follow-up period in comparison to discharge. No major adverse events, as defined per protocol, were observed during the intervention or during the follow-up period. Conclusions: The ChordArt device allows successful treatment of primary degenerative MR due to posterior mitral leaflet prolapse or flail, with a good safety profile and promising immediate clinical and echocardiographic benefits that are confirmed up to 24 months.

20.
Circulation ; 120(14): 1355-63, 2009 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-19770393

RESUMEN

BACKGROUND: The efficacy of granulocyte colony-stimulating factor (G-CSF) for coronary collateral growth promotion and thus impending myocardial salvage has not been studied so far, to our best knowledge. METHODS AND RESULTS: In 52 patients with chronic stable coronary artery disease, age 62+/-11 years, the effect on a marker of myocardial infarct size (ECG ST segment elevation) and on quantitative collateral function during a 1-minute coronary balloon occlusion was tested in a randomized, placebo-controlled, double-blind fashion. The study protocol before coronary intervention consisted of occlusive surface and intracoronary lead ECG recording as well as collateral flow index (CFI, no unit) measurement in a stenotic and a > or =1 normal coronary artery before and after a 2-week period with subcutaneous G-CSF (10 microg/kg; n=26) or placebo (n=26). The CFI was determined by simultaneous measurement of mean aortic, distal coronary occlusive, and central venous pressure. The ECG ST segment elevation >0.1 mV disappeared significantly more often in response to G-CSF (11/53 vessels; 21%) than to placebo (0/55 vessels; P=0.0005), and simultaneously, CFI changed from 0.121+/-0.087 at baseline to 0.166+/-0.086 at follow-up in the G-CSF group, and from 0.152+/-0.082 to 0.131+/-0.071 in the placebo group (P<0.0001 for interaction of treatment and time). The absolute change in CFI from baseline to follow-up amounted to +0.049+/-0.062 in the G-CSF group and to -0.010+/-0.060 in the placebo group (P<0.0001). CONCLUSIONS: Subcutaneous G-CSF is efficacious during a short-term protocol in improving signs of myocardial salvage by coronary collateral growth promotion.


Asunto(s)
Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Factor Estimulante de Colonias de Granulocitos/uso terapéutico , Anciano , Angina de Pecho/fisiopatología , Angioplastia Coronaria con Balón , Cateterismo Cardíaco , Enfermedades Cardiovasculares/epidemiología , Dolor en el Pecho/epidemiología , Enfermedad Crónica , Angiografía Coronaria , Método Doble Ciego , Ecocardiografía , Femenino , Humanos , Hiperemia , Masculino , Persona de Mediana Edad , Infarto del Miocardio/epidemiología , Isquemia Miocárdica/fisiopatología , Placebos , Factores de Riesgo
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