RESUMO
BACKGROUND: Formal international medical programmes (IMPs) represent an evolution away from traditional medical volunteerism, and are based on the foundation of bidirectional exchange of knowledge, experience and organizational expertise. The intent is to develop multidirectional collaborations and local capacity that is resilient in the face of limited resources. Training and accreditation of surgeons continues to be a challenge to IMPs, including the need for mutual recognition of competencies and professional certification. METHODS: MEDLINE, Embase and Google Scholar™ were searched using the following terms, alone and in combination: 'credentialing', 'education', 'global surgery', 'international medicine', 'international surgery' and 'training'. Secondary references cited by original sources were also included. The authors, all members of the American College of Academic International Medicine group, agreed advice on training and accreditation of international surgeons. RESULTS AND CONCLUSION: The following are key elements of training and accrediting international surgeons: basic framework built upon a bidirectional approach; consideration of both high-income and low- and middle-income country perspectives; sourcing funding from current sources based on existing IMPs and networks of IMPs; emphasis on predetermined cultural competencies and a common set of core surgical skills; a decentralized global system for verification and mutual recognition of medical training and certification. The global medical system of the future will require the assurance of high standards for surgical education, training and accreditation.
Assuntos
Acreditação/métodos , Cirurgia Geral/educação , Internato e Residência/métodos , Cirurgiões/educação , Saúde Global , Humanos , Estados UnidosRESUMO
Critical illness polyneuropathy and myopathy is associated with intensive care unit therapies; it is an independent predictor of mortality and will be increasingly affecting the practice of critical care. Most patients with this illness are over 50 years of age, and as our population demographics shift in favor of an aging population, physicians must be aware that this malady will have a rising incidence in the perioperative period. Intensivists, anesthesiologists, surgeons, and geriatricians/internists must remain vigilant. Here we present a concise overview of critical illness polyneuropathy and myopathy, its diagnosis, associations, and possible interventions.
RESUMO
Peak instantaneous power is a prognostic index of LV function but is difficult to measure. It is relatively load independent when corrected by preload (EDV2). Easier to acquire power estimates have been proposed--including mean and simplified power. These require only echo Doppler flow and cuff pressures, but their relationship to invasively derived results has not been studied. Using a well-validated numerical model of the cardiovascular system, different estimates of power were compared for varying preload, afterload, and contractility. All power results were divided by EDV2. Estimates of power correlate with peak power over a wide range of physiology. Corrected power estimates were independent of preload and afterload, but predictably increased with contractility. Different estimates of preload corrected power can be derived from non-invasively obtained variables and correlate with corrected peak instantaneous power.
Assuntos
Modelos Cardiovasculares , Contração Miocárdica/fisiologia , Função Ventricular Esquerda/fisiologia , Algoritmos , Pressão Sanguínea/fisiologia , Testes de Função Cardíaca , Humanos , Sístole/fisiologia , Pressão Ventricular/fisiologiaRESUMO
Previous studies relating Doppler parameters and pulmonary capillary wedge pressures (PCWP) typically exclude patients with severe mitral regurgitation (MR). We evaluated the effects of varying degrees of chronic MR on the Doppler estimation of PCWP. PCWP and mitral Doppler profiles were obtained in 88 patients (mean age 55 +/- 8 years) with severe left ventricular (LV) dysfunction (mean ejection fraction 23% +/- 5%). Patients were classified by severity of MR. Patients with severe MR had greater left atrial areas, LV end-diastolic volumes, and mean PCWPs and lower ejection fractions (each P <.01). In patients with mild MR, multiple echocardiographic parameters correlated with PCWP; however, with worsening MR, only deceleration time strongly related to PCWP. From stepwise multivariate analysis, deceleration time was the best independent predictor of PCWP overall, and it was the only predictor in patients with moderate or severe MR. Doppler-derived early mitral deceleration time reliably predicts PCWP in patients with severe LV dysfunction irrespective of degree of MR.
Assuntos
Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência da Valva Mitral/diagnóstico por imagem , Pressão Propulsora Pulmonar/fisiologia , Doença Crônica , Ecocardiografia Doppler , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/fisiopatologia , Hemodinâmica , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/complicações , Insuficiência da Valva Mitral/fisiopatologia , Índice de Gravidade de Doença , Disfunção Ventricular Esquerda/complicações , Disfunção Ventricular Esquerda/fisiopatologia , Pressão VentricularRESUMO
BACKGROUND: Early diastolic intraventricular pressure gradients (IVPGs) have been proposed to relate to left ventricular (LV) elastic recoil and early ventricular "suction." Animal studies have demonstrated relationships between IVPGs and systolic and diastolic indices during acute ischemia. However, data on the effects of improvements in LV function in humans and the relationship to IVPGs are lacking. METHODS AND RESULTS: Eight patients undergoing CABG and/or infarct exclusion surgery had a triple-sensor high-fidelity catheter placed across the mitral valve intraoperatively for simultaneous recording of left atrial (LA), basal LV, and apical LV pressures. Hemodynamic data obtained before bypass were compared with those with similar LA pressures and heart rates obtained after bypass. From each LV waveform, the time constant of LV relaxation (tau), +dP/dt(max), and -dP/dt(max) were determined. Transesophageal echocardiography was used to determined end-diastolic (EDV) and end-systolic (ESV) volumes and ejection fractions (EF). At similar LA pressures and heart rates, IVPG increased after bypass (before bypass 1.64+/-0.79 mm Hg; after bypass 2.67+/-1.25 mm Hg; P<0.01). Significant improvements were observed in ESV, as well as in apical and basal +dP/dt(max), -dP/dt(max), and tau (each P<0.05). Overall, IVPGs correlated inversely with both ESV (IVPG=-0.027[ESV]+3.46, r=-0.64) and EDV (IVPG=-0.027[EDV]+4.30, r=-0.70). Improvements in IVPGs correlated with improvements in apical tau (Deltatau =5.93[DeltaIVPG]+4.76, r=0.91) and basal tau (Deltatau =2.41[DeltaIVPG]+5.13, r=-0.67). Relative changes in IVPGs correlated with changes in ESV (DeltaESV=-0.97[%DeltaIVPG]+23.34, r=-0.79), EDV (DeltaEDV=-1.16[%DeltaIVPG]+34.92, r=-0.84), and EF (DeltaEF=0.38[%DeltaIVPG]-8.39, r=0.85). CONCLUSIONS: Improvements in LV function also increase IVPGs. These changes in IVPGs, suggestive of increases in LV suction and elastic recoil, correlate directly with improvements in LV relaxation and ESV.
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Pressão Sanguínea , Doença das Coronárias/fisiopatologia , Doença das Coronárias/cirurgia , Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Esquerda/fisiopatologia , Procedimentos Cirúrgicos Cardíacos , Diástole , Elasticidade , Técnicas Eletrofisiológicas Cardíacas , Feminino , Testes de Função Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Sístole , Resultado do TratamentoAssuntos
Insuficiência da Valva Aórtica/congênito , Valva Aórtica/anormalidades , Ponte de Artéria Coronária , Complicações Intraoperatórias/diagnóstico por imagem , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Valva Aórtica/transplante , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/cirurgia , Terapia Combinada , Ecocardiografia Transesofagiana , Humanos , Complicações Intraoperatórias/cirurgia , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND: Although long-term durability data exist, little data are available concerning the hemodynamic performance of the Carpentier-Edwards PERIMOUNT pericardial valve in the mitral position. METHODS: Sixty-nine patients who were implanted with mitral PERIMOUNT valves at seven international centers between January 1996 and February 1997 consented to participate in a short-term echocardiography follow-up. Echocardiographs were collected at a mean of 600+/-133 days after implantation (range, 110 to 889 days); all underwent blinded core lab analysis. RESULTS: At follow-up, peak gradients were 9.09+/-3.43 mm Hg (mean, 4.36+/-1.79 mm Hg) and varied inversely with valve size (p < 0.05). The effective orifice areas were 2.5+/-0.6 cm2 and tended to increase with valve size (p = 0.08). Trace mitral regurgitation (MR) was common (n = 48), 9 patients had mild MR, 1 had moderate MR, none had severe MR. All MR was central (n = 55) or indeterminate (n = 3). No paravalvular leaks were observed. Mitral regurgitation flow areas were 3.4+/-2.8 cm2 and were without significant volumes. CONCLUSIONS: In this multicenter study, these mitral valves are associated with trace, although physiologically insignificant, central MR. Despite known echocardiographic limitations, the PERIMOUNT mitral valves exhibit similar hemodynamics to other prosthetic valves.
Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Hemodinâmica/fisiologia , Valva Mitral/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Idoso , Causas de Morte , Ecocardiografia Doppler , Análise de Falha de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Insuficiência da Valva Mitral/mortalidade , Insuficiência da Valva Mitral/fisiopatologia , Insuficiência da Valva Mitral/cirurgia , Complicações Pós-Operatórias/mortalidade , Recidiva , Estudos Retrospectivos , Análise de SobrevidaRESUMO
Previous studies have shown that small intraventricular pressure gradients (IVPG) are important for efficient filling of the left ventricle (LV) and as a sensitive marker for ischemia. Unfortunately, there has previously been no way of measuring these noninvasively, severely limiting their research and clinical utility. Color Doppler M-mode (CMM) echocardiography provides a spatiotemporal velocity distribution along the inflow tract throughout diastole, which we hypothesized would allow direct estimation of IVPG by using the Euler equation. Digital CMM images, obtained simultaneously with intracardiac pressure waveforms in six dogs, were processed by numerical differentiation for the Euler equation, then integrated to estimate IVPG and the total (left atrial to left ventricular apex) pressure drop. CMM-derived estimates agreed well with invasive measurements (IVPG: y = 0.87x + 0.22, r = 0.96, P < 0.001, standard error of the estimate = 0.35 mmHg). Quantitative processing of CMM data allows accurate estimation of IVPG and tracking of changes induced by beta-adrenergic stimulation. This novel approach provides unique information on LV filling dynamics in an entirely noninvasive way that has previously not been available for assessment of diastolic filling and function.
Assuntos
Pressão Sanguínea/fisiologia , Diástole/fisiologia , Ecocardiografia/métodos , Modelos Cardiovasculares , Função Ventricular Esquerda/fisiologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Cardiotônicos/administração & dosagem , Simulação por Computador , Cães , Isoproterenol/administração & dosagem , Modelos Lineares , Reprodutibilidade dos Testes , Função Ventricular Esquerda/efeitos dos fármacosRESUMO
The pressure-velocity relationship across the normal mitral valve is approximated by the Bernoulli equation DeltaP = 1/2 rhoDeltav(2) + M. dv/dt, where DeltaP is the atrioventricular pressure difference, rho is blood density, v is transmitral flow velocity, and M is mitral inertance. Although M is indispensable in assessing transvalvular pressure differences from transmitral flow, this term is poorly understood. We measured intraoperative high-fidelity left atrial and ventricular pressures and simultaneous transmitral flow velocities by using transesophageal echocardiography in 100 beats (8 patients). We computed mean mitral inertance (M) by M = integral((DeltaP)-(1/2 x rho v(2))dt/integral(dv/dt)dt and we assessed the effect of the inertial term on the transmitral pressure-flow relation. ranged from 1.03 to 5.96 g/cm(2) (mean = 3.82 +/- 1.22 g/cm(2)). DeltaP calculated from the simplified Bernoulli equation (DeltaP = 1/2. rhov(2)) lagged behind (44 +/- 11 ms) and underestimated the actual peak pressures (2.3 +/- 1.1 mmHg). correlated with left ventricular systolic pressure (r = -0.68, P < 0.0001) and transmitral pressure gradients (r = 0.65, P < 0.0001). Because mitral inertance causes the velocity to lag significantly behind the actual pressure gradient, it needs to be considered when assessing diastolic filling and the pressure difference across normal mitral valves.
Assuntos
Pressão Sanguínea/fisiologia , Ecocardiografia Doppler/métodos , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiologia , Pressão Ventricular/fisiologia , Adulto , Idoso , Diástole/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
BACKGROUND AND AIM OF THE STUDY: The non-invasive evaluation of mitral valve area is often used in the assessment of patients with mitral stenosis. The pressure half-time method is commonly used to calculate valve area, but is inaccurate in many clinical scenarios. We sought to quantify the effects of changing cardiac output on the accuracy of mitral valve area determination. METHODS: Thirteen patients with mitral stenosis underwent routine stress echocardiography with resting and peak exercise results compared. A previously described and clinically validated mathematical model of the cardiovascular system was used to validate the clinical results. Seven different loading conditions for each of four different stenotic valve areas were modeled. RESULTS: In patients, with increasing cardiac output, pressure half-time decreased (-30.6+/-35.3 ms/l/min) and calculated valve area increased by 0.25+/-0.30 cm2/l/min. By continuity, it appeared that approximately half of this increase was due to actual valve orifice stretching, the remainder reflecting fundamental changes in the relationship between half-time and valve area. Mathematical modeling resulted in similar changes in pressure half-time and calculated valve area (0.06 to 0.12 cm2/l/min, p = 0.20 versus clinical results). CONCLUSION: Changes in cardiac output result in predictable changes in pressure half-time, and should be considered when performing serial examinations in patients with mitral stenosis.
Assuntos
Pressão Sanguínea/fisiologia , Débito Cardíaco/fisiologia , Ecocardiografia , Teste de Esforço , Estenose da Valva Mitral/diagnóstico por imagem , Valva Mitral/diagnóstico por imagem , Adulto , Idoso , Simulação por Computador , Diástole/fisiologia , Ecocardiografia Doppler , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Estenose da Valva Mitral/fisiopatologia , Modelos Teóricos , Volume Sistólico/fisiologia , Sístole/fisiologia , Função Ventricular Esquerda/fisiologiaRESUMO
Shortened early transmitral deceleration times (E(DT)) have been qualitatively associated with increased filling pressure and reduced survival in patients with cardiac disease and increased left ventricular operating stiffness (K(LV)). An equation relating K(LV) quantitatively to E(DT) has previously been described in a canine model but not in humans. During several varying hemodynamic conditions, we studied 18 patients undergoing open-heart surgery. Transesophageal echocardiographic two-dimensional volumes and Doppler flows were combined with high-fidelity left atrial (LA) and left ventricular (LV) pressures to determine K(LV). From digitized Doppler recordings, E(DT) was measured and compared against changes in LV and LA diastolic volumes and pressures. E(DT) (180 +/- 39 ms) was inversely associated with LV end-diastolic pressures (r = -0.56, P = 0.004) and net atrioventricular stiffness (r = -0.55, P = 0.006) but had its strongest association with K(LV) (r = -0.81, P < 0.001). K(LV) was predicted assuming a nonrestrictive orifice (K(nonrest)) from E(DT) as K(nonrest) = (0.07/E(DT))(2) with K(LV) = 1.01 K(nonrest) - 0.02; r = 0.86, P < 0.001, DeltaK (K(nonrest) - K(LV)) = 0.02 +/- 0.06 mm Hg/ml. In adults with cardiac disease, E(DT) provides an accurate estimate of LV operating stiffness and supports its application as a practical noninvasive index in the evaluation of diastolic function.
Assuntos
Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Idoso , Diástole , Ecocardiografia Doppler , Feminino , Ventrículos do Coração/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/diagnóstico por imagem , Estenose da Valva Mitral/fisiopatologia , Volume SistólicoRESUMO
Myocardial tissue Doppler echocardiography (TDE) has been proposed as a tool for the assessment of diastolic function. Controversy exists regarding whether TDE measurements are influenced by preload. In this study, left ventricular volume and high-fidelity pressures were obtained in eight closed-chest dogs during intermittent caval occlusion. The time constant of isovolumic ventricular relaxation (tau) was altered with varying doses of dobutamine and esmolol. Peak early diastolic myocardial (E(m)) and transmitral (E) velocities were measured before and after preload reduction. The relative effects of changes in preload and relaxation were determined for E(m) and compared with their effects on E. The following results were observed: caval occlusion significantly decreased E (DeltaE = 16.4 +/- 3.3 cm/s, 36.6 +/- 13.7%, P < 0.01) and E(m) (DeltaE(m) = 1. 3 +/- 0.4 cm/s, 32.5 +/- 26.1%, P < 0.01) under baseline conditions. However, preload reduction was similar for E under all lusitropic conditions (P = not significant), but these effects on E(m) decreased with worsening relaxation. At tau < 50 ms, changes in E(m) with preload reduction were significantly greater (DeltaE(m) = 2.8 +/- 0.6 cm/s) than at tau = 50-65 ms (DeltaE(m) = 1.2 +/- 0.2 cm/s) and at tau >65 ms (DeltaE(m) = 0.5 +/- 0.1 cm/s, P < 0.05). We concluded that TDE E(m) is preload dependent. However, this effect decreases with worsening relaxation.
Assuntos
Circulação Coronária , Ecocardiografia , Contração Miocárdica/fisiologia , Função Ventricular Esquerda , Animais , Velocidade do Fluxo Sanguíneo , Constrição Patológica , Diástole , Cães , Valva Mitral/fisiologia , Pressão , Veias Cavas/fisiopatologia , Função VentricularRESUMO
Assessment of left ventricular filling pressure usually requires invasive hemodynamic monitoring to follow the progression of disease or the response to therapy. Previous investigations have shown accurate estimation of wedge pressure using noninvasive Doppler information obtained from the ratio of the wave propagation slope from color M-mode (CMM) images and the peak early diastolic filling velocity from transmitral Doppler images. This study reports an automated algorithm that derives an estimate of wedge pressure based on the spatiotemporal velocity distribution available from digital CMM Doppler images of LV filling.
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Algoritmos , Ecocardiografia Doppler em Cores/métodos , Pressão Propulsora Pulmonar/fisiologia , Função Ventricular Esquerda/fisiologia , Adulto , Cateterismo Cardíaco , Simulação por Computador , Átrios do Coração/diagnóstico por imagem , Humanos , Pressão Negativa da Região Corporal Inferior , Masculino , Valva Mitral/diagnóstico por imagem , Modelos Cardiovasculares , PressãoRESUMO
Efforts to improve mitral regurgitation (MR) are often performed in conjunction with coronary revascularization. However, the independent effects of a reduced MR area (MRa) are difficult to quantify. Using a previously developed cardiovascular model, ventricular contractility (elastance 1-8 mmHg/ml) and relaxation (tau: 40-150 msec) were independently adjusted for four grades of MR orifice areas (0.0 to 0.8 cm2). Improvements in forward stroke volume (fSV) were determined for the permutations of reduced MRa. For all conditions, LV end-diastolic pressure and volumes ranged from 7.3-24.2 mmHg and 64.8-174.3 ml, respectively. Overall, fSV ranged from 36.0-89.4 (mean: 64.2 +/- 12.8) ml, improved between 6.4 and 35.3% (mean: 15.6 +/- 8.1%), and was best predicted by (r=0.97, p<0.01) %delta(fSV)[correction of fVS]=34[MRa initial] - 46[MRa final] -0.5[elastance]. Reduced MRa, independent of relaxation and minimally influence by contractility, yield improved fSVs.
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Pressão Sanguínea/fisiologia , Diástole/fisiologia , Insuficiência da Valva Mitral/fisiopatologia , Modelos Cardiovasculares , Volume Sistólico/fisiologia , Sístole/fisiologia , Hemodinâmica/fisiologia , Humanos , Índice de Gravidade de DoençaRESUMO
Inertial forces (Mdv/dt) are a significant component of transmitral flow, but cannot be measured with Doppler echo. We validated a method of estimating Mdv/dt. Ten patients had a dual sensor transmitral (TM) catheter placed during cardiac surgery. Doppler and 2D echo was performed while acquiring LA and LV pressures. Mdv/dt was determined from the Bernoulli equation using Doppler velocities and TM gradients. Results were compared with numerical modeling. TM gradients (range: 1.04-14.24 mmHg) consisted of 74.0 +/- 11.0% inertial forcers (range: 0.6-12.9 mmHg). Multivariate analysis predicted Mdv/dt = -4.171(S/D (RATIO)) + 0.063(LAvolume-max) + 5. Using this equation, a strong relationship was obtained for the clinical dataset (y=0.98x - 0.045, r=0.90) and the results of numerical modeling (y=0.96x - 0.16, r=0.84). TM gradients are mainly inertial and, as validated by modeling, can be estimated with echocardiography.
Assuntos
Ecocardiografia Doppler/estatística & dados numéricos , Valva Mitral/diagnóstico por imagem , Valva Mitral/fisiopatologia , Modelos Cardiovasculares , Disfunção Ventricular Esquerda/diagnóstico por imagem , Idoso , Ponte Cardiopulmonar , Diástole , Ecocardiografia Doppler/métodos , Feminino , Gravitação , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/fisiopatologia , Pressão VentricularRESUMO
OBJECTIVES: We hypothesized that color M-mode (CMM) images could be used to solve the Euler equation, yielding regional pressure gradients along the scanline, which could then be integrated to yield the unsteady Bernoulli equation and estimate noninvasively both the convective and inertial components of the transmitral pressure difference. BACKGROUND: Pulsed and continuous wave Doppler velocity measurements are routinely used clinically to assess severity of stenotic and regurgitant valves. However, only the convective component of the pressure gradient is measured, thereby neglecting the contribution of inertial forces, which may be significant, particularly for nonstenotic valves. Color M-mode provides a spatiotemporal representation of flow across the mitral valve. METHODS: In eight patients undergoing coronary artery bypass grafting, high-fidelity left atrial and ventricular pressure measurements were obtained synchronously with transmitral CMM digital recordings. The instantaneous diastolic transmitral pressure difference was computed from the M-mode spatiotemporal velocity distribution using the unsteady flow form of the Bernoulli equation and was compared to the catheter measurements. RESULTS: From 56 beats in 16 hemodynamic stages, inclusion of the inertial term ([deltapI]max = 1.78+/-1.30 mm Hg) in the noninvasive pressure difference calculation significantly increased the temporal correlation with catheter-based measurement (r = 0.35+/-0.24 vs. 0.81+/-0.15, p< 0.0001). It also allowed an accurate approximation of the peak pressure difference ([deltapc+I]max = 0.95 [delta(p)cathh]max + 0.24, r = 0.96, p<0.001, error = 0.08+/-0.54 mm Hg). CONCLUSIONS: Inertial forces are significant components of the maximal pressure drop across the normal mitral valve. These can be accurately estimated noninvasively using CMM recordings of transmitral flow, which should improve the understanding of diastolic filling and function of the heart.
Assuntos
Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/fisiopatologia , Valva Mitral/fisiologia , Ultrassonografia Doppler em Cores , Função Ventricular Esquerda , Pressão Ventricular , Idoso , Feminino , Hemodinâmica , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Análise de RegressãoRESUMO
OBJECTIVES: We sought to determine the relationship between different echocardiographic indices and pulmonary capillary wedge pressures (PCWP) in normal volunteers. BACKGROUND: Indices based on tissue Doppler (TDE) and color M-mode (CMM) echocardiography have been proposed to reflect left (LV) ventricular filling pressures. These include the ratio of early diastolic transmitral velocity (E) to early myocardial velocity measured by TDE (E') and the ratio of E to the wave propagation velocity (Vp) measured from CMM images. These indices, however, have not been validated in normal individuals. METHODS: We studied seven volunteers during two phases of preload altering maneuvers, baseline, with two stages of lower body negative pressure, and repeat baseline with two stages of volume loading. The PCWP obtained from right heart catheterization was compared with diastolic indices using pulsed Doppler, TDE and CMM echocardiography. RESULTS: The PCWP ranged from 2.2 to 23.5 mm Hg. During preload alterations, significant changes in E and septal E' (both p < 0.05) but not lateral E' or Vp were observed. Furthermore, E, septal E' and E/Vp correlated with PCWP (all r > 0.80) but not combined E and TDE indices (both r < 0.15). Within individuals, a similar linear relationship was observed among E/Vp, E and septal E' (average r > 0.80). CONCLUSIONS: In subjects without heart disease, E, septal E' and E/Vp correlate with PCWP. Because the influence of ventricular relaxation is minimized, the ratio E/Vp may be the best overall index of LV filling pressures.
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Ecocardiografia , Pressão Propulsora Pulmonar/fisiologia , Adulto , Feminino , Humanos , Masculino , Valores de ReferênciaRESUMO
Coronary aneurysms in adults are rare. Surgical treatment is often concomitant to treating obstructing coronary lesions. However, the ideal treatment strategy is poorly defined. We present a case of successful treatment of a large coronary artery aneurysm with a reverse saphenous interposition vein graft. This modality offers important benefits over other current surgical and percutaneous techniques and should be considered as an option for patients requiring treatment for coronary aneurysms.
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Aneurisma Coronário/cirurgia , Ponte de Artéria Coronária , Veias/transplante , Adulto , Idoso , Aneurisma Coronário/diagnóstico por imagem , Angiografia Coronária , Feminino , Humanos , Complicações Pós-Operatórias/diagnóstico por imagemRESUMO
BACKGROUND: Infarct exclusion (IE) surgery, a technique of left ventricular (LV) reconstruction for dyskinetic or akinetic LV segments in patients with ischemic cardiomyopathy, requires accurate volume quantification to determine the impact of surgery due to complicated geometric changes. METHODS AND RESULTS: Thirty patients who underwent IE (mean age 61+/-8 years, 73% men) had epicardial real-time 3-dimensional echocardiographic (RT3DE) studies performed before and after IE. RT3DE follow-up was performed transthoracically 42+/-67 days after surgery in 22 patients. Repeated measures ANOVA was used to compare the values before and after IE surgery and at follow-up. Significant decreases in LV end-diastolic (EDVI) and end-systolic (ESVI) volume indices were apparent immediately after IE and in follow-up (EDVI 99+/-40, 67+/-26, and 71+/-31 mL/m(2), respectively; ESVI 72+/-37, 40+/-21, and 42+/-22 mL/m(2), respectively; P:<0.05). LV ejection fraction increased significantly and remained higher (0.29+/-0.11, 0.43+/-0.13, and 0.42+/-0.09, respectively, P:<0.05). Forward stroke volume in 16 patients with preoperative mitral regurgitation significantly improved after IE and in follow-up (22+/-12, 53+/-24, and 58+/-21 mL, respectively, P:<0.005). New York Heart Association functional class at an average 285+/-144 days of clinical follow-up significantly improved from 3.0+/-0.8 to 1.8+/-0.8 (P:<0.0001). Smaller end-diastolic and end-systolic volumes measured with RT3DE immediately after IE were closely related to improvement in New York Heart Association functional class at clinical follow-up (Spearman's rho=0.58 and 0.60, respectively). CONCLUSIONS: RT3DE can be used to quantitatively assess changes in LV volume and function after complicated LV reconstruction. Decreased LV volume and increased ejection fraction imply a reduction in LV wall stress after IE surgery and are predictive of symptomatic improvement.