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PubMed2006

Impact of myocardial perfusion on left atrial remodeling following primary angioplasty for acute myocardial infarction.

OBJECTIVES: To investigate the impact of myocardial perfusion on left atrial remodeling and its determinants after primary percutaneous coronary intervention for acute myocardial infarction. BACKGROUND: Left atrial volume is an important predictor of morbidity and mortality in acute myocardial infarction, while thrombolysis in myocardial infarction (TIMI) myocardial perfusion (TMP) grade is an angiographic index associated with infarct size and mortality. As yet, however, the relationship between TMP grade and left atrial remodeling has not been investigated. METHODS: Conventional transthoracic echocardiography was performed in 105 patients (55+/-13 years old, 92 men) with acute myocardial infarction within 24 h and after 6 months (mean 9+/-4, range 6-29 months) following successful primary percutaneous coronary intervention. Absolute left atrial volume was calculated using an elliptical model. Myocardial perfusion was evaluated, using TMP grade, by visual assessment on the coronary angiogram. Patients were divided into three groups on the basis of myocardial perfusion status, as TMP 0/1 (n=36), TMP 2 (n=36) and TMP 3 (n=33). RESULTS: No difference was observed between baseline and follow-up left atrial volumes in the overall study population (42.5+/-16.1 vs. 43.5+/-17.4 ml, P=0.519). As regards TMP grade, follow-up left atrial volume significantly increased in the TMP 0/1 group (43+/-17 vs. 54.6+/-1.1 ml, P<0.001) and significantly decreased in the TMP 3 group (42.9+/-15.7 vs. 35.5+/-12.2 ml, P=0.001) compared with initial values. No change was observed in left atrial volume in the TMP 2 group. Multivariate analysis showed that TMP grade (P<0.001) and anterior location of myocardial infarction (P<0.001) were independent determinants of left atrial remodeling. CONCLUSIONS: These results suggest that poor myocardial perfusion and anterior location of myocardial infarction can affect left atrial remodeling in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention. It appears that adequate myocardial perfusion is crucial to prevent left atrial remodeling, a poor prognostic factor in acute myocardial infarction.

Adult↗
PubMedDate not supplied

Assessment of left atrial appendage flow velocity and its relation to spontaneous echocardiographic contrast in 89 cats with myocardial disease.

The hypotheses of this prospective study were that (1) left atrial appendage (LAA) blood flow velocities can be recorded in cats with myocardial disease by transthoracic Doppler echocardiography, (2) LA enlargement, LA mechanical dysfunction, and left ventricular (LV) diastolic abnormalities are associated with decreased LAA flow velocities, and (3) low LAA flow velocities predict the appearance of spontaneous echocardiographic contrast in cats with cardiomyopathy. Transthoracic 2-dimensional, M-mode, and Doppler echocardiographic studies were performed in 89 cats with hypertrophic, restrictive, dilated, or unclassified cardiomyopathy or with hyperthyroid heart disease. Maximal LAA flow velocity (LAAmax) was decreased (P < .001) in cats with cardiomyopathy (median, 0.28 m/s; range, 0.08-1.35) compared to normal cats. Associated with decreased LAA flow velocities were increased LA size, decreased LA function, increased severity of LV diastolic dysfunction, and the presence of congestive heart failure. Multivariate logistic regression analysis detected an LAAmax <0.20 m/s as the only independent variable to predict LA spontaneous echocardiographic contrast (odds ratio, 30.1; 95% confidence interval [CI], 4.1 222.3; P < .001). Receiver operating characteristic analysis performed to predict spontaneous echocardiographic contrast indicated an area under the curve of 0.88 (95% CI, 0.80-0.95; P < .001) with sensitivities of 100 and 74% and specificities of 69 and 83% for LAAmax <0.25 and <0.20 m/s, respectively. Thus, low LAA flow velocities identified a subgroup of patients at increased risk of spontaneous echocardiographic contrast and possible thromboembolism. These findings may have important clinical implications for anticoagulation therapy and prognostication in cats with cardiomyopathy.

Animals↗
PubMed2006

Stentless mitral valve implantation in comparison to conventional mitral valve repair or replacement at five years.

OBJECTIVE: A chordally supported stentless mitral valve (SMV) may be a suitable prosthesis for patients with severe degenerative mitral valve disease. We analyzed the five-year results and compared them with results after conventional mitral valve repair or replacement. METHODS: 155 patients, operated on since August 1997, were evaluated. 53 patients (ages, 68 +/- 8 years, 37 female, valve repair not feasible) received a SMV (Quattro), 51 patients (69 +/- 9 years, 32 female) had mitral valve repair (MVR) and 51 patients (66 +/- 9 years, 32 female) had a conventional mitral valve replacement (MVP). There were no significant differences with respect to preoperative NYHA functional class, left ventricular ejection fraction, cardiac index and surgical risk, according to the EuroSCORE. Mean follow-up is 64 +/- 18 (21-89) months. RESULTS: Surgery was performed using a median sternotomy (32 [SMV]/20 [MVR]/34 [MVP]) or a lateral mini-thoracotomy 21/31/17 approach. The SMV was safely attached to the papillary muscles. In-hospital mortality was 1, 2 and 4 respectively; re-operation was required in 6, 2 and 3 patients. Five-year survival rate was 80.6 +/- 4.4 % (SMV), 80.2 +/- 5.6 % (CMV) and 82.6 +/- 5.6 % (MVP), p = n.s. After hospital discharge, there was no significant difference in mortality in comparison to an age-matched control population. Echocardiography revealed acceptable SMV hemodynamics with preservation of left ventricular function. CONCLUSION: Midterm results after SMV implantation are comparable to conventional approaches. Complete preservation of the annulo-ventricular continuity is advantageous and close to physiologic hemodynamics can be achieved. Long term follow-up is required.

Aged↗
PubMed2003

Working heart function in diabetes is not improved by spironolactone treatment.

Aldosterone antagonism has emerged as an important strategy for end-stage congestive heart failure. To evaluate the potential contribution of aldosterone towards the cardiac complications of diabetes, this study examined the effects of chronic aldosterone receptor blockade (with spironolactone) on isolated working heart function in streptozotocin (STZ) - induced diabetic rats. Wistar rats were divided into four groups: control, control spironolactone-treated, diabetic, and diabetic spironolactone-treated. Following chronic spironolactone treatment (8 weeks), cardiac function was assessed in terms of the rate of contraction (+dP/dT), rate of relaxation (-dP/dT), and left ventricular developed pressure (LVDP). Untreated diabetic rats exhibited marked cardiac dysfunction when compared with age matched controls (p < 0.001). Long-term spironolactone treatment did not improve these parameters. These data demonstrate the lack of beneficial effects of aldosterone receptor blockade on isolated working heart function in diabetes.

Animals↗
PubMed2005

The left atrial appendage, a small, blind-ended structure: a review of its echocardiographic evaluation and its clinical role.

The increasing prevalence of stroke and atrial fibrillation is a stimulus for new therapeutic strategies and also warrants a review of imaging modalities of the most important source of cardiac systemic embolic events: the left atrial appendage (LAA). This blind-ended, complex structure is embryologically distinct from the body of the left atrium and is sometimes regarded as just a minor extension of the atrium. However, it should routinely be analyzed as part of a transesophageal echocardiographic (TEE) examination. A pulsed Doppler TEE analysis of LAA emptying flow should supplement a two-dimensional (2-D) analysis; these examinations have proven to be highly reproducible and to help assess thromboembolic risk. In 2-D imaging, potential thrombus and spontaneous echo contrast should be sought. In addition, LAA plays a hemodynamic role that participates in atrial function and is influenced by various hemodynamic conditions. In view of the embolic risks from a dysfunctional appendage, the LAA is often ligated during cardiac valve surgery. New devices are under evaluation for percutaneous closure of the LAA, and further studies should improve the definition, understanding, and treatment of LAA dysfunction.

Age Factors↗
PubMedDate not supplied

Proposal of a working left heart model with a heterotopic transplantation technique in rats.

BACKGROUND: A heterotopically transplanted rat heart model described by Ono and Lindsey in 1969 has been widely used as a fundamental animal model of heart transplantation. However this "nonworking" model is greatly different from the orthotopic heart in view of left ventricular work, in which the experimental results obtained may not always reflect the clinical setting with an orthotopic transplanted "working" heart. We herein propose a new "working" left heart model in rats using a heterotopic abdominal transplantation technique by modifying the method of Ono and Lindsey. METHODS: First, a donor heart graft and a recipient were prepared in the conventional fashion. Second, the donor heart was tailored by the ligation of main pulmonary artery and the removal of tricuspid valve and interatrial septum. Third, the ascending aorta and right atrium of the donor heart were anastomosed to the infrarenal abdominal aorta and to the inferior vena cava of the recipient, respectively. Consequently, the left atrium and ventricle of heart graft were loaded with the blood from the right atrium through the interatrial communication. RESULTS: This surgical procedure required an average of 58 minutes and had negligible operative risk. The donor left ventricle produced a systolic blood pressure almost equal to the recipient's aortic pressure and maintained vigorous beat. CONCLUSIONS: This model is easily reproducible and would be useful for various studies on heart transplantation.

Animals↗
PubMed1993

[Transvenous monitoring of left atrial and central venous pressure with a double-lumen catheter].

We developed a new method to monitor left atrial pressure in the patients undergoing open heart surgery. The advantages of our method are 1) freedom from complications relating its removal (eg. bleeding) because of its transvenous insertion, and 2) simultaneous monitoring of both right and left atrial pressures by a single catheter. We designed to place the second port of a two-lumen central venous catheter 5 or 7 cm proximal to the tip. The catheter is inserted into the right atrium before surgery and the tip is advanced in the left atrium through the foramen ovale intraoperatively. We used this catheter in 16 infants and children, and found that effective hemodynamic monitoring was obtained without any complications. We recommend this method for the postoperative management of open heart surgery in the pediatric patients.

Atrial Function, Left↗
PubMed1987

Right ventricular function: a comparison between blood and crystalloid cardioplegia.

Blood cardioplegia resulted in better left ventricular (LV) function than crystalloid cardioplegia after elective coronary artery bypass operations. However, most methods of cardioplegic delivery may not adequately cool and protect the right ventricle, and right ventricular (RV) dysfunction may limit hemodynamic recovery. Therefore, RV and LV temperatures were measured intraoperatively and RV and LV function were evaluated postoperatively in 80 patients with double-vessel or triple-vessel coronary artery disease who were randomized to receive either blood cardioplegia or crystalloid cardioplegia. Myocardial performance, systolic function, and diastolic function were assessed with nuclear ventriculography by evaluating the response to volume loading. Preoperatively the groups were similar. Intraoperatively, blood cardioplegia resulted in significantly warmer LV and RV temperatures (left ventricle: 15.5 degrees +/- 0.2 degrees C with blood cardioplegia and 12.6 degrees +/- 0.3 degrees C with crystalloid cardioplegia [p less than .0001]; right ventricle: 18.3 degrees +/- 0.3 degrees C with blood cardioplegia and 15.1 degrees +/- 0.3 degrees C with crystalloid cardioplegia [p less than .0001]). Postoperatively, blood cardioplegia resulted in better LV performance (higher LV stroke work index at a similar LV end-diastolic volume index [EDVI]) (p = .01), better LV systolic function (similar systolic blood pressures at smaller LV end-systolic volume indexes [ESVI]), (p = .04), and improved LV diastolic function (lower left atrial pressures at similar LVEDVIs) (p = .03).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Pressure↗
PubMed2004

Total heart volume variation throughout the cardiac cycle in humans.

Variations in total heart volume (atria plus ventricles) during a cardiac cycle affect efficiency of cardiac pumping. The goals of this study were to confirm the presence, extent, and contributors of total heart volume variation during the cardiac cycle in healthy volunteers with the use of MRI. Eight healthy volunteers were examined by MRI at rest. Changes in total cardiac volume throughout the cardiac cycle were calculated using the following methods: 1) planimetry derived from gradient-echo cine images and 2) flow-sensitive sequences to quantify flow in all vessels leading to and from the heart. The maximum total heart volume diminished during systole by 8.2 +/- 0.8% (SEM, range 4.8-10.6%) measured by method 1 and 8.8 +/- 1.0% (SEM, range 5.6-11.8%) by method 2 with good agreement between the methods [difference according to Bland-Altman analysis -0.6% +/- 1.0% (SD), intraclass correlation coefficient = 0.999]. This decrease in volume is predominantly explained by variation at the midcardiac level at the widest diameter of the heart with a left-sided predominance. In the short axis of the heart, the change of slice volume was proportional to the end-diastolic slice volume. The present study has confirmed the presence of total heart volume variation that predominantly occurs in the region of atrioventricular plane movement and on the left side. The total heart volume variation may relate to the efficiency of energy use by the heart to minimize displacement of surrounding tissue while accounting for the energy required to draw blood into the atria during ventricular systole.

Adult↗
PubMed1991

Left atrial isomerism in the adolescence: report of two cases.

Atrial isomerism is very rare in adolescence. Two cases of left atrial isomerism are reported here in 2 females, aged 21 and 19 years. They had presented with cyanosis and dyspnea since childhood. High kilovoltage filter films showed a bilateral morphologically left bronchus. Cardiac catheterization in Case 1 revealed normal pulmonary artery pressure, severe subvalvular pulmonic stenosis, a double outlet right ventricle, a significant oxygen step-up at the atrial level and moderate systemic oxygen desaturation; while Case 2 disclosed pulmonary hypertension and mild systemic oxygen desaturation. Both cases had the following anatomical features: ipsilateral connection of pulmonary veins to the bilateral morphological left atrium; interrupted inferior vena cave with azygos or hemiazygos continuation; total anomalous hepatic venous return to the right-sided atrium; complete atrioventricular canal. The diagnoses were confirmed in both cases at surgical correction.

Adult↗
PubMed1995

[Effects of erythrocytopheresis on the state of the left heart in patients with polycythemia vera: echocardiographic findings].

Functional response of the left ventricle (LV) and left atrium to erythrocytapheresis (EA) was studied in 20 patients. At admission, the patients had enlarged LV and low myocardial contractility. By cardiac and stroke volume indices two types of central hemodynamics were identified (hyperkinetic and hypokinetic) dependent on PV duration and concomitant cardiac pathology. These correlations were inferred basing on comparisons of echo-CG findings to data on the patients' age, sex, PV history, associated heart disease, packed cell volume. EA produced positive changes in echo-CG indices with complete normalization of cardiac output in some cases. This is supposed to be due to EA ability to limit foci of myocardial damage and to mobilize cardiac reserves.

Aged↗
PubMed1994

Effects of nicardipine, nitroglycerin, and nitroprusside on left ventricular diastolic function during enflurane anesthesia.

The purpose of this study was to evaluate the effects of nicardipine (NCR), nitroglycerin (NTG), or nitroprusside (SNP) on left ventricular diastolic function during enflurane anesthesia in acutely instrumented dogs. Using echocardiography, time constants for the decline in isovolumic left ventricular pressure (T), stiffness constant (K), diastolic time intervals, and left ventricular filling rates were measured in 21 mongrel dogs during the following conditions: (1) 0% enflurane (control), (2) 3.3% enflurane, (3) intravenous infusion of NCR, 1 microgram/kg/min, NTG, 2 micrograms/kg/min, or SNP, 2 micrograms/kg/min, during 3.3% enflurane, and (4) intravenous infusion of NCR, 2 micrograms/kg/min, NTG, 4 micrograms/kg/min, or SNP, 4 micrograms/kg/min, during 3.3% enflurane. During 3.3% enflurane anesthesia, T and K increased significantly, and left ventricular filling rates decreased. The administration of NCR, NTG, or SNP returned T and K to control levels. Left ventricular rapid filling rate returned toward the control level only with NCR (P < 0.05, NCR v NTG, SNP). It is concluded that the depression of diastolic function during enflurane anesthesia was improved by NCR or other vasodilators. The extent and mechanism of action of these vasodilators might differ, however.

Anesthesia, Inhalation↗
PubMed2000

Left ventricular apical puncture: a procedure surviving well into the new millennium.

We report two patients with a history of prior mitral valve and aortic valve replacement with St. Jude prosthetic valves, who were referred for repeat valve replacement after noninvasive assessment was suggestive of prosthetic valve malfunction. Both patients were managed medically after evaluation with direct left ventricular apical puncture revealed normal hemodynamics in the first and mild aortic stenosis in the second patient. These two cases illustrate that, despite the advancements in the noninvasive evaluation of prosthetic heart valves, left ventricular direct puncture continues to have an important value in the evaluation of patients referred for repeat valve replacement, and it can prevent unnecessary surgeries associated with a high risk of morbidity and mortality. Cathet. Cardiovasc. Intervent. 49:68-73, 2000.

Aortic Valve↗
PubMed1994

Usefulness of the pulmonary vein flow velocity-time profile as an estimate of left atrial storage fraction.

During ventricular systole, the left atrium (LA) stores a certain amount of ventricular stroke volume; this is defined as an LA storage volume. From cineangiocardiograms, an LA storage fraction is obtained as the ratio of the LA storage volume to left ventricular stroke volume. From the pulmonary vein (PV) flow velocity-time profile, the LA storage fraction may be estimated as a ratio of the PV flow velocity-time integral during systole (Sa) to a sum of that during systole and diastole (Sa+Da), namely, Sa/(Sa+Da), provided that the PV cross-sectional area remains relatively unchanged during one cardiac cycle and that the PV flow velocity-time profile is similar in any of the PVs draining to the LA. To evaluate usefulness of Doppler echocardiographic method of estimating the LA storage fraction, the authors measured the LA storage fraction from the left upper PV flow velocity-time profile by transesophageal Doppler echocardiography and compared it with the LA storage fraction from conventional cineangiocardiographic volumes. Subjects were 23 patients with a variety of cardiac diseases in normal sinus rhythm, ranging from eighteen to seventy-four years of age. The LA storage fraction was 0.58 +/- 0.12 (mean +/- SD) from cineangiocardiography and 0.64 +/- 0.08 from Doppler echocardiography larger than that from cineangiocardiography (P < 0.01), the correlation was good (r = 0.643). The authors conclude that the left upper PV flow velocity-time profile appears to provide a better correlation with that by cineangiography and may be used as a reliable quantitative estimate of the LA storage fraction.

Adult↗
PubMed2000

Wall stress and hypertension.

The precise role that abnormal wall stress may play in the pathophysiology of hypertensive heart disease is not known. Hypertension is almost unique in that it ultimately affects all parts of the law of Laplace equation, i.e. intraventricular pressure changes and with the advent of left ventricular hypertrophy both internal radius and wall thickness alter. If heart failure supervenes the components of the equation change once more. This article will discuss the implications of abnormal wall stress at these various stages in hypertensive heart disease.

Antihypertensive Agents↗
PubMed2000

The effect of transient balloon occlusion of the mitral valve on left atrial appendage blood flow velocity and spontaneous echo contrast: a comparison in sinus rhythm and atrial fibrillation patients.

OBJECTIVE: To investigate the relationship between spontaneous echo contrast (SEC) and left atrial appendage (LAA) blood flow velocity using transesophageal echocardiography (TEE) during percutaneous balloon mitral valvotomy (PBMV) in patients with atrial fibrillation and sinus rhythm. METHODS: Thirty-five patients (21 in sinus rhythm and 14 in atrial fibrillation) with rheumatic mitral stenosis underwent PBMV with intraoperative transesophageal echocardiography monitoring. We measured LAA blood flow velocities and observed the left atrium for various grades of SEC (from 0 = none to 4 = severe), before and after each balloon inflation. RESULTS: Left atrial appendage maximal emptying velocity (LAA MEV) was reduced from 35 +/- 14 cm/s to 6 +/- 2 cm/s at peak balloon inflation and increased to 40 +/- 16 cm/s after balloon deflation. Comparison of the values before balloon inflation and after balloon deflation showed that LAA velocities were significantly lower (P < 0.001). During balloon inflation, both maximal emptying velocity (MEV) and maximal filling velocity (MFV) were significantly decreased, compared to those before inflation and after balloon deflation (P < 0.01). And both MEV and MFV were significantly higher after balloon deflation relative to those before balloon inflation. Patients with atrial fibrillation had significantly lower MEV and MFV before and during balloon inflation and after balloon deflation than patients with sinus rhythm. At peak balloon inflation, new or increased SEC grades were observed during 54 of 61 (88%) inflations and unchanged during 7 (12%) inflations. SEC grades were reduced after 55 balloon deflations (90%), completely disappeared after 18 deflations (30%) and remained unchanged after 6 deflations (10%). At peak balloon inflation, left atrium spontaneous echo contrast (LASEC) grade 4 was observed during 14 of 27 (93%) inflations in the atrial fibrillation patients, significantly higher than in patients with sinus rhythm (8 of 34, 24%; P < 0.05). LASEC completely disappeared after 16 of 34 deflations (47%) in the patients with sinus rhythm, significantly higher than in the atrial fibrillation patients (2 of 27 deflations; P < 0.01). The mean time to achieve maximal SEC grade (2.5 +/- 1.2 s) correlated with the mean time to trough LAA velocities (2.3 +/- 1.1 s) after balloon inflation. Both the time to lowest LAA velocity and the time to highest LASEC were significantly longer in the patients with sinus rhythm than in the atrial fibrillation patients (2.6 +/- 1.1 s vs 1.7 +/- 1.0 s, P < 0.05 and 2.8 +/- 1.4 s vs 1.9 +/- 1.3 s, P < 0.05, respectively). Upon deflation, the mean time to lowest SEC grade (2.9 +/- 1.8 s) correlated with the mean time to achieve maximal LAA velocities (2.7 +/- 1.6 s). Both intervals are significantly shorter in the patients with sinus rhythm than in the atrial fibrillation patients (2.0 +/- 1.6 s vs 3.5 +/- 1.5 s, P < 0.01 and 2.2 +/- 1.7 s vs 3.6 +/- 1.6 s, P < 0.05). CONCLUSION: Reducing the blood flow velocity in the human left atrium by balloon occlusion of the mitral valve may enhance SEC, whereas restoring blood flow after balloon deflation would cause enhanced echogenic blood to disappear or decrease in both groups of patients. Patients with atrial fibrillation demonstrate more severe blood stagnation of the left atrial body and appendage during transient balloon inflation at mitral valve orifice and slower recovery from the stagnation, decreasing to a lesser extent after balloon deflation, when compared to patients with sinus rhythm.

Adolescent↗
PubMed1995

[Does mitral insufficiency prevent spontaneous contrast phenomenon and formation of thrombi in the left atrium?].

The aim of this study was to assess the influence of mitral regurgitation on the prevalence of left atrial spontaneous echo contrast and thrombosis in 2,180 consecutive patients undergoing transthoracic and transoesophageal echocardiography. Two groups of patients were defined according to the absence (group I) or presence (group II) of grades 3 or 4 mitral regurgitation quantified by transoesophageal echocardiography. Group II was associated with a statistically significant lower frequency of spontaneous echo contrast (0.6 vs 11.2%; p < 0.0001), left atrial thrombosis (0.6 vs 4.2%; p < 0.03), ischaemic cerebrovascular accidents (1.2 vs 21%; p < 0.0001), transient ischaemic attacks (0 vs 12%; p < 0.0001) and systemic embolism (0 vs 4.6%; p < 0.01). Conversely, the prevalence of atrial fibrillation was higher in group II (28 vs 19%; p < 0.01) and there were more patients with left atrial dimensions > or = 5.5 cm (16 vs 6.7%; p < 0.0001). When mitral stenosis and valve prosthesis were excluded, there were no cases of spontaneous echo contrast (8.3 vs 0%; p < 0.001) or left atrial thrombosis (2.9 vs 0%; p < 0.05) in the group with grades 3 or 4 mitral regurgitation. The phenomenon of left atrial spontaneous echo contrast and/or thrombosis is rare in patients with grade 3 or 4 in native mitral valve regurgitation and explains the low incidence of systemic embolism in these cases.

Adolescent↗
PubMed2005

Acute effects of suction retraction on atrial hemodynamics and histology.

OBJECTIVES: In minimally invasive and robotic mitral valve surgery, a blade retractor is used to elevate the left atrial roof, which often distorts tissue and impairs visualization. We tested the hemodynamic and histologic changes of intra-atrial suction, using a new suction retractor that may improve stabilization and visualization. METHODS: Swine were divided into 3 equal (n = 4) groups: blade retractor, suction retractor, and arrested heart control. Left atrial ultrasonic crystals were used to record ejection fractions. After cardioplegic arrest, the atrium was opened and sampled for preretractor histology. Retractors remained in place for 1 hour, followed by postretractor histologic sampling. Controls were crossclamped for an equivalent time and postarrest histologic data obtained. Animals were weaned from bypass, data were collected for 4 hours, and postsacrifice atrial histologic samples were obtained. RESULTS: The main effect due to treatment was not statistically significant ( P = .52) between the 3 groups, with the 4-hour average ejection fraction for blade retractor, suction retractor, and control being statistically equivalent at 33.3% +/- 8.3, 35.3% +/- 12.1, and 40.8% +/- 9.9 (mean +/- standard deviation), respectively. Histology showed equivalent amounts of myocyte fragmentation, interstitial edema, eosinophilia, and wavy fibers between blade retraction and suction retraction, while the latter showed slightly increased amounts of hemorrhage. CONCLUSIONS: Atrial endocardial suction retraction appears to be safe with no acute changes in the left atrial ejection fraction or significant acute histologic differences, compared to blade retraction. Furthermore, intra-atrial suction may be applicable to procedures other than minimally invasive and robotic mitral valve repair for providing improved stabilization.

Animals↗