面积应变评价冠心病患者左心室整体收缩功能

目的：应用超声三维斑点追踪成像（3D-STI）技术获取冠心病患者左心室整体应变参数,评价冠心病患者左心室整体收缩功能及其临床应用价值。方法冠心病患者30例,对照组20例。经胸采集心尖全容积三维图像,应用三维斑点追踪分析软件测量两组病例左室整体长轴应变值（GLS）、整体圆周应变值（GCS）、整体径向应变值（GRS）及整体面积应变值（GAS）。分析两组间各参数的差异并对各参数与左室射血分数（LVEF）之间的相关性进行分析。结果与对照组比较,冠心病组GRS、GCS、GLS、GAS较对照组明显减低,差异有统计学意义（t=2.79,P＜0.01;t=2.73,P＜0.01;t=3.70,P＜0.001;t=3.40,P＜0.001）。ROC曲线分析GRS、GCS、GLS、GAS诊断冠心病的敏感性分别为65.7%、63.2%、75.6%、83.9%,特异性分别为62.3%、64.2%、69.1%、75.8%,GAS诊断冠心病心肌缺血的敏感性和特异性最高。GLS、GCS、GAS与LVEF之间呈负相关。r分别为-0.632、-0.671、-0.656,均为P＜0.001;GRS与LVEF之间呈正相关,r为0.629,P＜0.001。结论3D-STI技术测量的面积应变等参数能较敏感地评价冠心病患者早期左室整体收缩功能的变化。     

Effects of mitral valve replacement on regional left ventricular systolic strain.

BACKGROUND: Mitral valve replacement (MVR) with chordal excision impairs left ventricular (LV) systolic function, but the responsible mechanisms remain incompletely characterized. Loss of normal annular-papillary continuity also adversely affects LV torsional deformation, possibly due to changes in myocardial fiber contraction pattern. METHODS: Twenty-seven dogs underwent insertion of LV myocardial markers and a sham procedure (cardiopulmonary bypass, no MVR, n = 6), conventional MVR with chordae tendineae excision (n = 7), or chordal-sparing MVR with reattachment of the anterior leaflet chordae to the anterior annulus (n = 7) or to the posterior annulus (n = 7). In the anterior, lateral, posterior, and septal LV regions, linear chords were constructed from each region's central marker to its surrounding markers. Percent systolic shortening (regional LV strain) was calculated for each chord, and the chords were assigned to one of four angular groups: I, left-handed oblique (subepicardial fiber direction); II, circumferential (midwall); III, right-handed oblique (subendocardial); or IV, longitudinal. Regional LV strain data were compared before and after MVR. RESULTS: Sham and anterior chordal-sparing MVR had minimal effects on regional LV strain. With posterior chordal-sparing MVR: anteriorly, left-oblique (I) strain fell (31%, p<0.05), as did circumferential (II) and right-oblique (III) strains (by 49% and 51%, respectively; p<0.01). Laterally, left-oblique (I) strain fell by 36% (p<0.05), as did longitudinal (IV) strain (54% decline, p<0.01). Conventional MVR with chordal excision disrupted regional fiber shortening diffusely, affecting oblique fibers (I and III) in the anterior and septal regions and impairing longitudinal (IV) strain in all regions (45% to 68% fall, p<0.05). CONCLUSIONS: Sham and anterior chordal-sparing MVR did not substantially alter regional LV strain; however, loss of normal anatomic valvular-ventricular integrity (conventional MVR) or posterior chordal-sparing MVR resulted in pronounced alterations in LV strain, most notably in the longitudinal and oblique fiber directions. These findings demonstrate that the deleterious effects of chordal excision are associated with perturbed internal myocardial systolic deformation, which suggests that chordal disruption distorts myofiber architecture or regional systolic loading.     

Differential effects of isoflurane on regional right and left ventricular performances, and on coronary, systemic, and pulmonary hemodynamics in the dog

The effects of isoflurane-induced hypotension to mean aortic pressures of 70 and 55 mmHg on global and regional right (RV) and left (LV) ventricular performance (ultrasonic dimension technique), and on coronary, systemic, and pulmonary hemodynamics (electromagnetic flow probes) were studied in 12 open-chest dogs anesthetized and paralyzed by continuous infusions of fentanyl and pancuronium. Isoflurane caused dose-dependent decreases in LV and RV dP/dt, and in myocardial segment shortening in the presence of unchanged heart rate, unchanged or increased (RV) preload, and unchanged (RV) or decreased (LV) afterload. RV and LV functions were affected differently: at a mean aortic pressure of 70 mmHg (mean inspired isoflurane 1.2%), RV end diastolic dimensions and pressure remained unchanged, whereas those of the LV decreased. At a mean aortic pressure of 55 mmHg (mean inspired isoflurane 1.8%), RV end diastolic dimensions and pressure increased above control, whereas those of the LV remained unchanged. Within the RV, inflow and outflow tract were affected quantitatively similarly, but dyssynchrony developed in four animals. Isoflurane caused dose-dependent decreases in coronary and systemic vascular resistances, but no change in pulmonary vascular resistance. At the lower concentration of isoflurane, coronary blood flow did not fall despite decreased LV and RV dP/dt, unchanged heart rate, unchanged or decreased preload, and unchanged or reduced afterload. The data indicate that isoflurane is a myocardial depressant and a potent coronary vasodilator. At both concentrations, LV function was better preserved than RV function, most likely due to the different effects of isoflurane on RV (unchanged) and LV (reduced) afterload.     

Usefulness of strain cardiac magnetic resonance for the exposure of mild left ventricular systolic abnormalities in pectus excavatum

BackgroundSystolic dysfunction in pectus excavatum (PEX) is usually very subtle and mainly focused on the right ventricle (RV), leading to normal or unremarkable cardiac imaging findings unless involving exercise stress.ObjectivesWe evaluated systolic function in PEX using longitudinal strain cardiac magnetic resonance (CMR), a validated parameter for the assessment of the systolic deformation of subendocardial fibers.MethodsThis prospective registry comprised consecutive patients with PEX who were referred to CMR to define treatment strategies or to establish surgical candidacy. We also included a control group of 15 healthy volunteers without chest wall abnormalities. Using dedicated software, we evaluated the endocardial global longitudinal strain (GLS) of both ventricles and the endocardial global circumferential strain (GCS) of the left ventricle (LV).ResultsA total of 50 patients with PEX comprised the study population, with a mean age of 19.9 ± 8.0 years. The right ventricular ejection fraction (RVEF) of patients with PEX was significantly lower compared to the control group both at end-expiration (59.5 ± 6.8 vs. 64.7 ± 4.7%, p = 0.008) and end-inspiration (56.7 ± 7.2%, vs. 62.7 ± 4.4, p = 0.004); as well as the pulmonary stroke distance (12.6 ± 2.5, vs. 15.0 ± 2.0 cm, p = 0.001). The LV volumetric analysis revealed no differences between PEX and the control group (p > 0.05 for all) regardless of the respiratory cycle, with a mean expiratory LV ejection fraction (LVEF) of 61.4 ± 6.0%. In contrast, the GLS of the LV was significantly lower in PEX compared to controls (-21.2 ± 3.2 vs. -23.7 ± 3.0%, p = 0.010), whereas GCS was similar either at expiration (-28.5 ± 4.0%, vs. -29.5 ± 2.8, p = 0.38) or inspiration (-29.3 ± 4.1%, vs.-28.9 ± 2.3, p = 0.73).ConclusionsIn this study, we demonstrated that longitudinal strain analysis might enable the detection of very subtle left ventricular systolic function abnormalities in patients with PEX, that are commonly overlooked using the conventional assessment.Level of evidenceII     

Acute stunning effect of hemodialysis on myocardial performance: A three-dimensional speckle tracking echocardiographic study

The effects of acute changes during hemodialysis (HD) on the myocardium are not yet known. The invention of three-dimensional speckle tracking echocardiography (3DSTE) has offered clinicians a new method to assess the movements of ventricular segments simultaneously in three spatial directions. The aim of this study was to evaluate the effect of first weekly standard HD process on the left ventricle (LV) and right ventricle (RV) global and regional myocardial function in patients with normal left ventricle ejection fraction using 3DSTE-derived indices. Patients (n=38) receiving maintenance HD in our clinic who have no known cardiovascular disease are examined just before and after a HD session using 3DSTE. Demographic and comorbidity data, renal replacement treatment characteristics, and laboratory test results are recorded. 3DSTE analysis is performed to calculate the LV global longitudinal, circumferential area and radial peak systolic strain, as well as RV septum and free-wall longitudinal strain and fractional area change. Patients are aged 52.8 ± 13.6 years and 52.6% of them are male. Mean dialysis duration is 56 months. The LV strain values of the patients changed markedly before and after HD (GLS: −14.2 ± 5.2, −11.1 ± 4.6 [P < .001], GCS: −14.8 ± 4.2, −12.4 ± 5.28 [P < .009]; GRS: 41.5 ± 16, 33.3 ± 16.5 [P = .003]; AREA −24.7 ± 7.2, −20.1 ± 7.6 [P = .001], respectively). We could not demonstrate any improvement in RV strain values before or after HD. LV strain values are positively correlated with blood pressure variability during the dialysis sessions. LV function is preserved better after HD in patients on beta or calcium channel blocker therapy compared to those who do not use these agents (P < .001, P < .01, respectively). HD treatment results in deterioration in all LV strain directions but not in RV. Strain assessment may improve vascular risk stratification of patients on chronic HD.     

三维斑点追踪成像评估化疗致卵巢癌患者左心室功能损伤

目的观察三维斑点追踪成像(3D-STI)评估紫杉醇联合卡铂对卵巢癌患者左心室功能影响的价值。方法对30例卵巢癌术后接受紫杉醇联合卡铂化学治疗(简称化疗)患者(卵巢癌组)分别于化疗前及化疗3、6周期后行3D-STI检查,以同期30名正常女性为对照组,获取左心室射血分数(LVEF)、左心室整体纵向应变(GLS)、圆周应变(GCS)、左心室扭转角度(LVtw)、扭矩(Tor)及纵向与圆周应变显像舒张指数(L-SI-DI、C-SI-DI),计算心肌综合指数(MCI)。采用受试者工作特征(ROC)曲线评价3D-STI参数对化疗致左心室收缩功能损害的诊断效能。结果卵巢癌组化疗前LVEF、GLS、GCS、LVtw、Tor、MCI、L-SI-DI及C-SI-DI与对照组差异均无统计学意义(P均>0.05),化疗3、6周期后上述参数均较对照组及化疗前降低,且化疗6周期后下降更显著(P均<0.05)。GLS、LVtw、Tor及MCI诊断化疗致左心室收缩功能损伤的AUC均>0.800(P均<0.05),其敏感度、特异度均>60.00%,约登指数均>0.50;其中MCI的AUC最大(0.907),Tor的敏感度最高(86.67%),GLS特异度最高(90.00%)。结论3D-STI可早期发现并量化评价紫杉醇联合卡铂化疗所致卵巢癌患者左心室功能损伤。     

The immediate hemodynamic effects of enhanced external counterpulsation on the left ventricular function

Abstract

Objectives. Enhanced external counterpulsation (EECP) is a non-invasive therapy with long-term anti-anginal effects offered to patients with refractory angina pectoris. The purpose of the present study was to investigate the effect of EECP on myocardial contractility measured as global longitudinal strain (GLS) during EECP treatment. Design. Patients with known refractory angina were enrolled by invitation and underwent 1 h of EECP treatment. Two-dimensional echocardiography and Doppler echocardiography were performed before and during EECP treatment with 15-minute intervals. The peak diastolic/systolic blood pressure ratio (D/S ratio) was monitored with finger pletysmography. GLS was assessed offline with speckle-tracking software (EchoPAC GE Healthcare USA). Results. Twenty patients were included (mean age 65.0 ± 8.2; 85% males). During EECP treatment, the systolic function of the left ventricle (LV) expressed in terms of an increasing GLS (? 17.9 vs. ? 16.2% p < 0.05) and a rising cardiac output (5.5 vs. 4.6 l/min p < 0.05) were improved. D/S ratio during the EECP procedure was inversely correlated to LV filling pressure (E/Em ratio r = ? 0.5 p = 0.035). Conclusions. In conclusion, we demonstrated that EECP improved left ventricular GLS and systolic function in an acute setting. Future studies must explore whether these immediate hemodynamic changes are associated to the clinical effect of EECP treatment.     

三维斑点追踪成像评估紫杉醇联合卡铂治疗卵巢癌患者左心室收缩功能

目的探讨三维斑点追踪成像(3D-STI)评估紫杉醇联合卡铂治疗卵巢癌患者左心室整体收缩功能的应用价值。方法对30例经病理确诊的卵巢癌患者(卵巢癌组)以紫杉醇联合卡铂化学治疗(简称化疗),于化疗前及化疗3、6个周期结束时行3D-STI,获取左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、左心室射血分数(LVEF)、球形指数(SPI)、左心室舒张末期质量(LVEDmass)、左心室收缩末期质量(LVESmass)及左心室整体纵向应变(GLS)、整体圆周应变(GCS)、整体径向应变(GRS)、整体面积应变(GAS),并与30名健康志愿者(对照组)进行对比。采用ROC曲线分析各应变参数对卵巢癌患者化疗后心功能受损的诊断效能。结果与对照组比较,卵巢癌组化疗3个和6个周期时LVEDV、LVEF降低,LVEDmass、LVESmass升高,左心室GLS、GCS、GRS、GAS均降低,且6个周期结束时更显著(P均0.05)。收缩期峰值应变参数诊断卵巢癌患者化疗后心功能的ROC曲线显示,化疗3个周期时GAS的AUC(0.944)及特异度(96.67%)均最高,GLS、GCS的敏感度最高(均为90.00%);化疗6个周期时GAS的AUC(0.953)及特异度(96.67%)最高,GLS的敏感度(93.33%)最高。结论 3D-STI可早期评估紫杉醇联合卡铂治疗卵巢癌患者左心室收缩功能。     

Challenges for ‘diastology’: contributions from Japanese researchers

Diastology is a study to treat diastole of the heart. Transmitral flow and pulmonary venous flow velocities recorded by pulsed Doppler echocardiography provide more important information about left ventricular (LV) diastolic dysfunction [left atrial (LA)?LV coupling] than cardiac catheterization in clinical practice; however, these waveforms are influenced by loading conditions, particularly preload. The early diastolic mitral annular and LV wall motion indices measured by tissue Doppler echocardiography can evaluate LV relaxation abnormality and filling pressure by being relatively preload independent. In addition, the role of concomitant systolic longitudinal dysfunction is well characterized in asymptomatic patients and in patients with heart failure and preserved ejection fraction. Two-dimensional speckle tracking echocardiography is an angle-independent method, and has the potential to evaluate the contraction and relaxation abnormalities in the longitudinal, circumferential, and radial directions of the LV myocardium as well as LV torsion/untwisting and, moreover, deformation of the LA myocardium and large arterial wall. As a result, this new technique can facilitate the early detection of impaired LA?LV?arterial coupling in patients before occurrence of overt heart failure symptoms.     

Left ventricular systolic strain in chronic kidney disease and hemodialysis patients

Background: The impact of chronic kidney disease (CKD) and hemodialysis on heart function is not fully understood. We aimed to investigate the influence of different stages of CKD and maintenance hemodialysis on heart function. Methods: One hundred fifty-three patients were categorized into 3 subgroups [56 without CKD as controls; 37 with moderate-advanced CKD, stages 3, 4 or 5, and 60 with end-stage renal disease (ESRD) undergoing maintenance hemodialysis]. Left ventricular (LV) function was assessed by conventional echocardiography and 2-dimensional speckle-tracking echocardiography with strain analysis (2D strain analysis). Results: There was no significant difference of gender, age and LV ejection fraction among groups. Compared with controls, global peak systolic longitudinal strain (GS(l)), circumferential strain and strain rate were decreased in the CKD group. Along with the decline of renal function, GS(l) deteriorated. Moreover, compared with moderate-advanced CKD patients, GS(l), circumferential strain and strain rate were better in ESRD group receiving maintenance hemodialysis. Conclusions: Worsening renal function was associated with a reduction of systolic function, and could be quantified by 2D strain analysis. The hemodialysis patients have better LV systolic function than the moderate-advanced CKD patients.     

Adverse effects of halothane in a canine model of acute right ventricular hypertension

The effects of acute right ventricular (RV) hypertension (RVH) induced by pulmonary artery (PA) constriction, and of two concentrations (mean inspired 0.8 and 1.5%) of halothane (HAL) during RVH on global and regional RV performance (ultrasonic dimension technique), and on coronary hemodynamics (electromagnetic flow probes) were studied in 12 open-chest dogs anesthetized and paralyzed by continuous infusions of fentanyl and pancuronium. Following PA constriction, RV systolic pressure more than doubled, RV end-diastolic and systolic dimensions increased, and stroke volume (SV) and segment shortening fell (P all less than 0.05). There was no evidence of regional myocardial dysfunction (i.e., akinesis, systolic lengthening, postsystolic shortening), and reactive hyperemia in response to right coronary artery occlusion was present. Subsequent addition of HAL (0.8%) resulted in further increases in end-diastolic and systolic dimensions, and in marked decreases in right coronary blood flow, segment shortening, SV, and aortic pressure. During HAL 1.5% (range: 1.2-1.6%), regional myocardial dysfunction developed in three animals, reactive hyperemia was abolished in five out of six animals tested, and metabolic acidosis developed. Release of PA constriction during 1.5% HAL in seven animals resulted in improved global and regional RV performance, disappearance of regional myocardial dysfunction, and restoration of reactive hyperemia. In this canine model of acute RVH, increasing concentrations of HAL led to increasing deterioration in global and regional RV performance most likely due to inadequate coronary perfusion.     

Exclusion of the non-functioning right ventricle in children with pulmonary atresia and intact ventricular septum

OBJECTIVE: A group of patients with pulmonary atresia and intact ventricular septum (PAIVS) have to undergo single ventricle repair. In these patients, the presence of the non-functioning right ventricle (RV) may lead to the aggravation of RV to coronary connections and left ventricular (LV) dysfunction. To prevent these deleterious effects, the RV was excluded surgically. METHODS: Between December 2000 and February 2006, 10 patients with PAIVS underwent RV exclusion in conjunction with cavo-pulmonary anastomosis (n=6) or systemic-to-pulmonary artery shunt (n=4). Median age at surgery was 5 months (range, 0.2-13.8). Median z-value of the tricuspid valve was -4.0 (range, -6.5 to -1.3). None had RV dependent coronary circulation. The tricuspid valve was closed directly or using a patch. Thrombotic materials were inserted into the RV cavity in eight patients. RESULTS: There was no mortality. Follow-up was completed in all patients for up to 79.1 months (median, 30.3). Seven patients underwent a Fontan procedure and the other three are waiting. Eight patients showed completely obliterated RV after exclusion. One of the two patients who had residual RV cavity underwent re-exclusion after a Fontan operation. Postoperative echocardiography revealed that LV end-diastolic dimension increased with borderline significance (p=0.050), whereas LV end-systolic dimension showed no significant changes. During follow-up, LV showed no evidence of regional ischemia or global dysfunction, and fractional shortening significantly increased compared with the pre-exclusion value (p=0.017). CONCLUSIONS: This study demonstrates that RV exclusion may be performed safely in a selected group of patients with PAIVS. This procedure may have beneficial effects on LV systolic function, by preventing possible ischemia, and on LV diastolic function, by obliterating the non-functioning cavity and improving the geometry of the ventricular septum.     

Myocardial ischemia during vasodilator therapy in a canine model of pulmonary hypertension and coronary insufficiency.

Pulmonary vasodilator therapy during increased right ventricular (RV) afterload and insufficient RV myocardial perfusion might further impair RV performance by lowering systemic and, thus, coronary perfusion pressure. This hypothesis was tested by initially inducing pulmonary hypertension (80% increase in resting pulmonary artery pressure by injection of autologous muscle) and subsequent right coronary artery stenosis (40% decrease in flow by external cuff occlusion) in eight open-chest dogs. Then the effects of nitroglycerin (5 micrograms.kg-1.min-1), prostaglandin E1 (0.2 microgram.kg-1.min-1), and hydralazine (mean 0.14 mg/kg) on global and regional (ultrasonic dimension technique) RV performance and coronary hemodynamics (electromagnetic flow probes) were determined. Following all three drugs, right coronary artery flow decreased by 40-65% (mean values) accompanied by severe regional myocardial dysfunction suggestive of ischemia (akinesis, systolic lengthening, and postsystolic shortening). Heart rates increased by 20-40%; aortic pressure decreased by 15-25%; and RV end-diastolic pressure remained unchanged. Despite similarly adverse effects on regional RV performance and comparable effects on heart rate, perfusion and filling pressures with all three drugs, RV systolic pressure, RV dP/dt, and pulmonary artery pressure during nitroglycerin and prostaglandin E1 remained unchanged, and stroke volume and pulmonary artery flow decreased, but they all increased or were maintained (stroke volume) during hydralazine. Gas exchange was not affected by any of the vasodilators. Thus, in this model of combined acute pulmonary hypertension and right coronary artery insufficiency, nitroglycerin, prostaglandin E1, and hydralazine elicited severe regional dysfunction suggestive of ischemia, probably related to concomitant increases in heart rate and decreases in coronary perfusion pressure. Despite such evidence of severe regional RV ischemia, hydralazine maintained global RV pump function. These results indicate 1) that in the presence of increased RV afterload and coronary insufficiency, reduction in coronary perfusion pressure during pulmonary vasodilator therapy may be deleterious, and 2) that even severe regional myocardial ischemia may not necessarily be accompanied by respective changes in global hemodynamics and thus may go undetected.     

Changes in cardiac dynamics by opening an interventricular shunt in dogs

Changes in right and left ventricular (RV, LV) dynamics caused by an interventricular shunt were examined in open-chest dogs. At a pulmonary to systemic blood flow ratio of 1.7 +/- 0.2 pulmonary flow increased by 53 +/- 13%, whereas aortic flow decreased by 9 +/- 2%. Shunt flow was continuous from the left to the right ventricle throughout the cardiac cycle, but 72 +/- 4% took place during the LV ejection phase. Peak systolic LV pressure declined by 6 +/- 3 mm Hg, LV end-diastolic segment length (SL) rose, and systolic shortening of the SL increased. Peak systolic RV pressure rose from 28 +/- 3 to 36 +/- 3 mm Hg and RV end-diastolic and end-systolic SL rose almost equally. Accordingly, RV systolic SL shortening did not rise despite the substantial augmentation in RV outflow. The transseptal end-diastolic pressure gradient did not rise, while the transseptal peak systolic gradient decreased when the shunt was opened. Similarly directed alterations were observed when the shunt was opened at different preloads and when the shunt flow was varied. Local work in the anterior wall of the right ventricle (calculated from the RV pressure SL loop) rose by 26 +/- 4%, whereas RV stroke work (product of mean systolic right ventricular pressure and pulmonary flow) rose by 57 +/- 12%; difference, P less than 0.05. LV stroke work and local work in anterior LV free wall rose in proportion when the shunt was opened.(ABSTRACT TRUNCATED AT 250 WORDS)     

三维斑点追踪成像评价糖尿病患者心脏损害的Meta分析

目的评价三维斑点追踪成像(3D-STI)定量测评糖尿病(DM)患者左心室应变的临床价值。方法计算机检索PubMed等数据库官方网站中2016年8月1日之前发表的有关3D-STI评价DM患者左心室功能的病例对照研究。确切的纳入与排除标准制定后,独立筛选文献、提取各项数据和评价质量分配给2名两名研究员。通过Stata 12.0软件分析权重均数差(WMD)及95%可信区间(CI)。结果最终纳入12篇病例对照研究,共计620例DM患者和473名正常者。Meta分析:DM组与对照组左心室射血分数的差异无统计学意义[WMD=-0.94,95%CI(-1.92,-0.04),P=0.06];左心室整体应变DM组与对照组相比差异均有统计学意义:径向应变[WMD=-3.63,95%CI(-5.15,-2.11),P0.01]、纵向应变[WMD=3.54,95%CI(2.71,4.36),P0.01]、环向应变[WMD 2.48,95%CI(1.49,3.48),P0.01]、面积应变[WMD=2.92,95%CI(2.33,3.50),P0.01)。结论 3D-STI定量测评糖尿病群体的左心室应变指标具有一定的临床价值。     

Anesthetic concerns in lung transplantation for severe pulmonary hypertension

Lung transplantation has become a consolidated treatment for patients with severe pulmonary hypertension (PH). Several difficulties are encountered during the procedure in such candidates, who are still recognized as more severely affected by perioperative morbility and mortality than those undergoing lung transplantation for other diseases. Right ventricular (RV) enlargement with tricuspid regurgitation, small left ventricle (LV) with an asymmetric hypetrophic wall, interventricular septal shift toward the left, with ventricular stiffness and diastolic incompetence, are typical preoperative echocardiographic findings of end-stage PH. A smooth induction and tracheal intubation will help prevent hypertensive crisis in highly susceptible candidates. Uncompensated vasodilatation or myocardial depression caused by anesthetics and mechanical ventilation may be responsible for acute RV dysfunction associated with low systemic blood pressure. Resuscitation and emergency adoption of cardiopulmonary by-pass (CPB) has been described for near-fatal anesthesia induction. Cardiovascular instability can develop after institution of one-lung ventilation and pulmonary artery clamping. An acute increase in pulmonary pressure results in a decrease in RV ejection fraction and then in acute RV failure. Interdependence of the right and left ventricles occurs such that RV function can alter LV function. Early detection of impending circulatory and/or respiratory deterioration is warranted to prevent an irreversible decline in cardiac output, resulting in hazardous cardiac arrest. Inhaled nitric oxide represents the first choice for treatment of PH and RV failure associated with systemic hypotension during lung transplantation. Intraoperative situations requiring CPB must be identified before development of systemic shock, which represents a late ominous sign of RV failure.     

Right ventricular dysfunction after coronary artery bypass grafting is a reality of unknown cause and significance

Objective: To evaluate the impact of coronary bypass surgery on the function of the right ventricle (RV) in patients with a pre-operative ejection fraction ≥ 35% who did not have any perioperative myocardial infarction.Method: We performed a prospective study of 30 patients who underwent uneventful isolated coronary artery bypass grafting (CABG). All patients had echocardiography prior to surgery and 3 months postoperatively. Myocardial tissue Doppler velocities were used to measure left and right ventricular function. The right ventricular myocardial performance index (Tei) and the ratio between the velocities of the RV and left ventricle (LV) were also calculated.Results: There was a significant improvement in left ventricular ejection fraction before and after CABG (P = .046). The tissue Doppler imaging (TDI) velocities from the LV remained unchanged, but highly significant reductions in right ventricular TDI velocities were observed (P <.001). The TDI peak systolic (S), early diastolic (E), and late diastolic (A) velocities had a reduction of 30%, 34.5%, and 20%, respectively. Similarly, a fall in RV to LV ratios of various TDI velocities was also observed. This was also accompanied by a significant rise in the RV Tei index. All of these findings are suggestive of significant RV dysfunction.Conclusion: There is a marked impairment of RV function after CABG.     

Local and global contractility of the right ventricle in ischemia of the free ventricular wall. An animal experiment study

Impaired right ventricular (RV) performance due to increased RV afterload in patients with sepsis or acute respiratory failure has been attributed to relative hypoperfusion and myocardial ischemia of the stressed free RV wall. There is evidence from experiments, however, that the normal RV is able to respond to a pressure load with adequate increases in myocardial blood flow. Whether or not ischemia of the free wall contributes to RV failure and whether restoration of RV perfusion can improve RV performance remains to be elucidated. The aim of this study was to compare local RV contractility to parameters of global RV contractility prior to and after induction of ischemia to its free wall. METHODS: Studies were performed in a total of 16 open-chest dogs using sonomicrometry to determine local contractility (velocity and percentage of fiber shortening) in the RV inflow tract (n = 8) prior to, 5, and 30 min after acute ligation of the right coronary artery (RCA). Parameters of global RV contractility (dP/dtmax, Vmax) were derived from intraventricular pressure measurements (tip-manometer). Regional myocardial blood flow (n = 6) was determined by the radioactive microsphere technique. Furthermore, the septal-lateral diameters of the RV (n = 8) and left ventricle (LV, n = 5), as well as the anterior-posterior diameter (n = 4) of the LV were measured simultaneously by use of sonomicrometers (Fig. 1); ventricular pressure-diameter diagrams were constructed in order to assess the dynamic geometry of the heart. RESULTS: Acute ligation of the RCA resulted in a reduction of myocardial blood flow (-39% to -72%), predominantly in the RV inflow tract (Table 1). The segment length of the RV free wall and diameter of the RV increased following RCA ligation (Fig. 3a) whereas the septal-lateral diameter of the LV decreased concomitantly. The LV anterior-posterior diameter remained unaffected (Table 2, Fig. 3b). While local RV contractility (percent shortening and velocity of fiber shortening) deteriorated (-40% and -32%, respectively), the parameters of global RV contractility (dP/dtmax, Vmax) remained unchanged (Fig. 4a). Heart rate, mean arterial pressure, RV systolic pressure, and LV filling pressure remained unchanged (Fig. 4b), whereas RV filling pressure increased (+52%) and cardiac output was reduced (-13%).(ABSTRACT TRUNCATED AT 400 WORDS)     

Assessment of cardiac performance using Tei indices in patients undergoing pulmonary thromboendarterectomy

BACKGROUND: This study was designed to evaluate left and right ventricular performance using Tei indices in patients with severe chronic thromboembolic pulmonary hypertension undergoing pulmonary thromboendarterectomy (PTE). The Doppler-derived indices are easily measurable indicators of ventricular function based on nongeometric assessment, which helps overcome some of the difficulties entailed in the geometric assessment of left ventricular (LV) and right ventricular (RV) function in pulmonary hypertension. METHODS: The indices were derived for 24 patients (aged 54+/-14 years) before and after PTE. Calculation of these indices was based on the duration of two time intervals using the formula (A - B)/B, where A is the interval between cessation and onset of mitral inflow (or tricuspid inflow) and B is LV or RV ejection time. In addition, LV and RV end-diastolic and end-systolic chamber areas were determined using two-dimensional echocardiography, and systolic function was calculated. Mean pulmonary artery pressure was determined invasively. RESULTS: PTE led to a significant reduction of mean pulmonary artery pressure (46+/-10 versus 25+/-6 mm Hg; p < 0.05). LV and RV indices were abnormally high before surgery, declined significantly afterwards, and then almost matched normal values (0.61+/-0.26 versus 0.37+/-0.18; p < 0.05 and 0.55+/-0.22 versus 0.37+/-0.13; p < 0.05). Geometric assessment of the left and right ventricle also showed impaired systolic function before PTE, with significant improvement after surgery. CONCLUSIONS: LV and RV Tei indices allow a quantitative assessment of ventricular function in patients undergoing PTE. Lower indices after surgery reflect an improvement of the previously impaired cardiac function. Our results emphasize the value of PTE in the treatment of chronic thromboembolic pulmonary hypertension.     

Echocardiographic assessment of right heart function in heart transplant recipients and the relation to exercise hemodynamics

This study aimed to characterize right heart function in heart transplantation (HTx) patients using advanced echocardiographic assessment and simultaneous right heart catheterization (RHC). Comprehensive two‐dimensional (2D) and three‐dimensional (3D) echocardiographic assessment of right heart function was performed in 105 subjects (64 stable HTx patients and 41 healthy controls). RHC was performed at rest and during semi‐supine maximal exercise test. Compared with controls, in conclusion, HTx patients had impaired right ventricle (RV) systolic function in terms of decreased RV‐free wall (FW) global longitudinal strain (GLS) (?20 ± 5% vs. ?28 ± 5%, P < 0.0001) and 3D‐ejection fraction (EF) (50 ± 8% vs. 60 ± 6%, P < 0.0001). In HTx patients, echocardiographic RV systolic function was significantly correlated with NYHA‐class (3D‐RVEF: r = ?0.62, P < 0.0001; RV‐FW‐GLS: r = ?0.41, P = 0.0009) and cardiac allograft vasculopathy (3D‐RVEF: r = ?0.42, P = 0.0005; RV‐FW‐GLS: r = ?0.25, P = 0.0444). RHC demonstrated a good correlation between invasively assessed resting RV‐stroke volume index and exercise capacity (r = 0.58, P < 0.0001) and NYHA‐class (r = ?0.41, P = 0.0009). RV systolic function is reduced in HTx patients compared with controls. 3D RVEF and 2D longitudinal deformation analyses are associated with clinical performance in stable HTx patients and seem suitable in noninvasive routine right heart function evaluation after HTx. Invasively assessed RV systolic reserve was strongly associated with exercise capacity.