Benefits of terminal noncardioplegic warm blood retrograde perfusion after terminal warm blood cardioplegia perfusion prior to aortic unclamping in open heart surgery

AIM: The benefits of terminal noncardioplegic warm blood retrograde perfusion (TNWB) and terminal warm blood cardioplegia perfusion (TWBC) after intermittent cold blood cardioplegia perfusion during aortic clamping were studied. METHODS: The clinical results of consecutive 128 patients who underwent on pump coronary artery bypass grafting (CABG) or valvular surgery were studied retrospectively. The aortic cross-clamp was removed (1) after five-minute TWBC and sequential three-minute TNWB in 59 patients (TNWB group), (2) immediately after five-minute TWBC in 29 patients (TWBC group), or (3) with neither TWBC or TNWB in 36 patients (control group). RESULTS: The incidence of spontaneous heart beat recovery was best in TNWB group, second in TNBC, and worst in control group (TNWB: 86, TWBC: 42, Control: 14%). The duration from aortic unclamping to heart beat recovery was shorter in TNWB group than TWBC group (TNWB: 2.1, TWB: 4.3 min). Cardiopulmonary bypass duration after aortic unclamping was shortest in TNWB group, second in TWBC group, and longest in control group (TNWB: 21.3, TWB: 27.5, Control: 46.9 min). The postoperative CPK-MB was lowest in TNWB group (TNWB: 65.3, TWB: 87.7, Control: 91.9U/L). Duration of intubation in TNWB group or TWBC group was shorter than control. CONCLUSIONS: Combination of the terminal noncardioplegic warm blood perfusion and terminal warm blood cardioplegic perfusion contributes to increase the incidence of spontaneous heart beat recovery, shortens cardiopulmonary bypass duration following aortic unclamping, and lowers postoperative CPK-MB.     

The intra-aortic cannula pump: A novel assist device for the acutely failing heart.

OBJECTIVE: The intra-aortic cannula pump is a catheter pump designed to support the acutely failing heart. It expels blood from the left ventricle into the ascending aorta in a pulsatile flow pattern. The aim of the study was to analyze the hemodynamic performance of this new intracardiac support system in acute heart failure. METHODS: A 24F cannula was studied in a series of 16 sheep. Hemodynamic changes were assessed in the nonfailing, the moderately failing, and the severely failing heart. Heart failure was induced by an injection of microspheres into the left anterior descending coronary artery. The cannula was inserted through the aortic arch and introduced through the aortic valve into the left ventricle. RESULTS: Cannula insertion was feasible in all animals. Flow through the intra-aortic cannula flow was increased to a maximum of 3 L/min. No hemodynamic changes were observed in the nonfailing heart. A significant increase in cardiac output was observed in the moderately and severely reduced left ventricle (2.67 +/- 0.7 L to 3.51 +/- 0.83 L; P =.001; and 1.18 +/- 0.77 L to 2.43 +/- 0.44 L; P =.001, respectively). A drop in left atrial pressure was achieved in moderate and severe heart failure (14.1 +/- 5.93 mm Hg to 9.71 +/- 2.63 mm Hg; P =.0001; and 23 +/- 7.16 mm Hg to 11.2 +/- 2.55 mm Hg; P = 0.0001, respectively). Systolic and diastolic systemic blood pressures increased in the severely failing heart (57.3 +/- 12.8 mm Hg to 75.4 +/- 11.2 mm Hg; P =.0001; and 35.6 +/- 8.2 mm Hg to 60 +/- 14.3 mm Hg; P =.0006, respectively). CONCLUSIONS: Hemodynamic data demonstrate the beneficial effects of the intra-aortic cannula pump in moderate and severe heart failure. The intra-aortic cannula pump represents a new modality for the treatment of acute heart failure.     

Efficacy and safety of on-pump beating heart surgery for valvular disease

BACKGROUND: This study was conducted to assess the efficacy and applicability of on-pump beating heart valvular operations using retrograde coronary sinus perfusion. METHODS: A prospective, randomized study was conducted. A total of 50 patients participated in this study after having been allocated to one of two groups. On-pump beating heart valvular operations using retrograde coronary sinus perfusion as myocardial protection were performed in 25 patients (beating heart procedure group: aortic = 8 patients, mitral = 15 patients, double = 2 patients). Twenty-five patients underwent conventional valvular operation using retrograde continuous warm blood cardioplegia (conventional procedure group: aortic = 9 patients; mitral = 13 patients; double = 3 patients). The remaining operative variables and early outcomes of these procedures were compared. In the beating heart procedure group, myocardial tissue oxygen was measured by near infrared spectroscopy, and partial oxygen pressure of coronary sinus perfusion was also measured. RESULTS: The visual field of the on-pump beating heart was equal to that of conventional valvular operation, and technical accuracy was not compromised. In the beating heart procedure group, tissue oxygen saturation was maintained at 79% +/- 2%, and partial oxygen pressure of coronary sinus perfusion blood and returned blood were maintained at 383 +/- 29 mm Hg and 38 +/- 2 mm Hg, respectively. Postoperative peak creatine kinase-MB (measured every 3 hours postoperatively) and peak troponin T concentrations were significantly lower than those of conventional procedures (17.5 +/- 7.8 vs 32.1 +/- 9.3 IU/L and 0.12 +/- 0.04 vs 0.21 +/- 0.06 ng/mL, respectively; p < 0.05). There was no operative mortality and no major complications. CONCLUSIONS: On-pump beating heart valvular operation is a good surgical option, and has advantages because conditions for the heart are more physiologic with beating tonus than with cardioplegia.     

Surgery for cardiac valves and aortic root without cardioplegic arrest ("beating heart"): experience with a new method of myocardial perfusion

Simultaneous antegrade/retrograde warm blood perfusion with a beating heart has not been previously reported as a mean of protecting hypertrophied hearts in cardiac valve and aortic root surgeries. Similarly, beating heart mitral valve surgery via the trans-septal approach with the aorta unclamped, is a novel technique. We, herein, report a series of 346 patients with a variety of cardiac pathologies who were operated upon utilizing a new modality of myocardial perfusion. Among this group of patients, there were 55 patients who were diagnosed with endocarditis of one or more valves. These patients were excluded from this series of patients. Mean age was 59 +/- 12, and there were 196 (67.3%) males and 95 (32.7%) females. There were six aortic root procedures, 90 mitral valve replacements (MVR), 46 mitral valve repairs, 20 MVR+ coronary artery bypass grafting (CABG), 28 tricuspid valve repairs, 106 aortic valve replacements (AVR), 17 AVR+CABG, and 8 AVR/MVR. Crude mortality for the group was 20 of 291 (6.8%). Intra-aortic balloon pump utilization at time of weaning from cardiopulmonary bypass was 6/291 (2.06%), and re-operation for bleeding was needed in 12 of 291 (4.1%) patients. Postoperative stroke occurred in 4 of 291 (1.3%) patients. In these patients, the clinical diagnosis of stroke was made prior to surgery. This initial experience with this new method of myocardial perfusion indicates that results are at least comparable, if not superior, to conventional techniques utilizing intermittent cold blood cardioplegia.     

Treatment of refractory coronary vasospasm during cardiopulmonary bypass with compulsory coronary perfusion.

Coronary vasospasm is still a devastating complication during cardiac surgery. We report on a case of intractable coronary vasospasm in a 45-year-old male during coronary bypass surgery refractory to drugs and intra-aortic balloon pumping (IABP). Under cardiopulmonary bypass (CPB) support, the aorta was again cross-clamped and the aortic root was compulsorily perfused with pump blood using a small pump for infusion of cardioplegia. Vasodilators were administered through the perfusion line. Coronary vasospasm was dramatically resolved. He was then successfully weaned from CPB and recovered without further incidents.     

Cold blood cardioplegia.

The technique of myocardial protection by means of a cardioplegic solution consisting of cold blood (10 degrees C) with potassium (30 mEq. per liter) is described. A disposable cooling coil is used and a separate pump head for coronary perfusion is avoided. The aortic perfusion cannula can be used for venting of the left ventricle and subsequently for venting of air. This method was used in 125 consecutive patients undergoing coronary revascularization and in 73 consecutive pediatric cardiac surgical procedures with excellent results.     

瓣膜病变合并冠状动脉病变外科治疗及围术期管理

目的 总结瓣膜病变合并冠状动脉病变的外科治疗及围术期管理经验。方法 对66例瓣膜病变合并冠状动脉病变病人的一般临床资料、术前心功能状态、冠状动脉病变相关因素、冠脉造影情况和手术结果进行分析。结果 围手术期死亡5例，死亡率为7.6%。结论 瓣膜病变合并冠状动脉病变的特点：⑴冠心病病史不常典型，必须重视术前冠状动脉造影检查。尤其年龄在45岁以上、来自冠心病高发区、即往有高血压、高血脂、糖尿病病史者。⑵术中心肌保护采用持续逆灌加间断顺灌。⑶手术重点放在再血管化分布范围广及对室壁运动有重要影响的分支。⑷瓣膜病变合并冠心病病人围术期心功能调整的重要原则是较好的处理心率（心律）、前负荷和后负荷以及心肌收缩力之间的综合关系。同时，治疗中严密注意电解质和酸碱平衡变化，及时酌情处理。     

Transapical Aortic Perfusion with a Double-Barreled Cannula

The transapical aortic perfusion method is a new approach to cardiopulmonary bypass and is performed with an infusion cannula placed in the ascending aorta through the left ventricular apex. The technique is applicable to almost all varieties of open-heart surgery, and is the most efficient method in infants and small children. A double-barreled forked cannula performs the two functions of aortic infusion and left ventricular decompression. With a Bakelite obturator, its cannulation to the aorta is very quick and easy.The transapical aortic perfusion method with a double-barreled cannula has been utilized in 156 open-heart operations with 17 perioperative fatalities and 1 late death. The 138 surviving patients have done well for periods up to four years.The perfusion method was developed from the left heart bypass and assisted circulation technique independently invented by Chardack's group and by us in 1966 and 1969, respectively.     

Pulsatile perfused porcine coronary arteries for microvascular training

Microsurgery is today an established technique in specialties such as plastic surgery, neurosurgery, and trauma surgery. However, specialized training is a prerequisite for mastering anastomosis of small-diameter vessels or coaptation of nerves in the operating room. The training should be as realistic as possible and thus, laboratory animals such as the rat are preferably used as a substitute. In an attempt to minimize the use of living animals without jeopardizing a realistic training setting, we developed a pulsatile perfused porcine coronary artery model for microsurgical education. The training model consists of a membrane pump that generates a pulsatile flow within a coronary artery of a porcine heart. The pump is commercially available with a dimension of approximately 130 x 100 x 60 mm and a weight of 190 g. The pump is energized by 220 B and the motor is run on a transformed power of approximately 12 V (range, 1.5-12 V). Different fluids from simple saline solution to theoretically whole blood can be used for perfusion. The membrane pump proved to be very reliable during microvascular training because of its convenient size and wide range of feed rate providing a very realistic training setting. A maximum fluid output of 850 mL/min can be achieved. The pump has a high acceptance in microsurgical trainees evaluated by questionnaires during several microsurgical courses. The pulsatile perfused porcine coronary artery system for microsurgical training enables the trainee to work under the most realistic training settings. It proved to be a valuable tool during microsurgical education, reducing the costs and sparing living laboratory animals. Thus, we can recommend this system to anyone who is involved in training and teaching microsurgical skills.     

Assessment of myocardial perfusion during CABG surgery with two-dimensional transesophageal contrast echocardiography

No reliable, quantifiable index of tissue perfusion is currently available to assess the efforts of coronary artery bypass graft (CABG) surgery. We used two-dimensional transesophageal contrast echocardiography with sonicated Renografin-76 microbubbles to determine the distribution of myocardial blood flow during coronary artery bypass graft surgery in 15 patients. Sonicated Renografin-76 contrast agent was injected into the aortic root of all patients after institution of cardiopulmonary bypass and application of the aortic occlusive clamp. Eight patients had contrast agent injected directly into the free proximal end of the vein-CABG anastomosis. All patients again received aortic root injections during reperfusion after anastomosis of the proximal aortovein and distal coronary artery. Echocardiographic images of the left ventricle short axis at the level of the papillary muscles were obtained in real time and analyzed retrospectively from videotape. Injection of contrast provided information about the magnitude and geometric distribution of coronary artery-vein bypass run-off and enabled identification of poorly perfused myocardial regions. When predicted myocardial perfusion patterns, based on preoperative evaluation of epicardial vessel distribution derived from coronary angiography, were compared to actual perfusion patterns assessed with intraoperative echocardiography, contrast regional myocardial perfusion patterns were predicted 84% of the time (71-97%, 95% confidence limit). Regional myocardial perfusion deficits detected after coronary bypass grafting were associated with regional wall motion abnormalities detected after separation from cardiopulmonary bypass. Our technique makes possible on-line visualization of changes in regional blood flow in the heart before, during, and after CABG.(ABSTRACT TRUNCATED AT 250 WORDS)     

Aortic valve replacement with on-pump beating heart technique

BACKGROUND: The aim of this study was to assess the efficacy and applicability of on-pump beating heart aortic valve replacement with retrograde coronary sinus (CS) warm blood perfusion. METHODS: The prospective study included 14 consecutive patients who underwent aortic valve replacement with mechanical prosthesis using retrograde CS perfusion. The operative variables and early outcome of this procedure are presented. RESULTS: Retrograde CS perfusion and venting the heart from the pulmonary vein provided good visualization of the operative field and performance of the operations without any difficulty. Partial oxygen pressures of CS perfusion blood and the returning blood from the coronary ostia were 288.5 +/- 34.4 and 39.6 +/- 4.6 mmHg, respectively. Postoperative peak creatine kinase-MB and troponin T values were mean 77.0 +/- 63.6 IU/L and mean 0.8 +/- 0.7 ng/mL, respectively. No mortality or major complication was observed and all the patients were discharged from the hospital in good condition. CONCLUSIONS: On-pump beating heart aortic valve replacement with retrograde CS warm blood perfusion is a good surgical option, and has the advantage of maintaining physiologic condition of the heart throughout the procedure.     

心脏移植术中供心的保护

目的 为了提高心脏移植的效果,改进心脏移植中供心的保护方法。方法 ３例原位心脏移植手术中采用４℃改良Ｓｔ,Ｔｈｏｍａｓ液经主动脉根部灌注和温血２６￣３４℃逆行状静脉窦灌注方法保护供心。结果 主动脉开放后,各项血液动力学指标在正常范围、心肌超微结构保持完整,未见缺血损害,长期随访心功能Ⅰ级,恢复正常生活和工作。结论 温血逆行冠状静脉窦灌注适合心脏移植中供心的保护。     

Isolated myocardial perfusion during arch repair

Repair of coarctation of the aorta with severe hypoplasia of the aortic arch or interrupted aortic arch was performed in 5 patients using a modification of the usual technique that consisted of isolated myocardial perfusion during arch repair. The aortic cross-clamp was placed on the ascending aorta distal to the aortic cannula. Cardiopulmonary bypass flow was reduced to about 10% of full flow, achieving a line pressure of 35 to 45 mm Hg to keep the heart perfused and beating during arch repair. Once the aortic arch was repaired, total body perfusion was continued as usual and intracardiac repair was performed. Isolated myocardial perfusion for aortic arch reconstruction reduces myocardial ischemic time.     

A new device: the quick cannulation system

We describe a new technique for the placing and fixing of extracorporeal circulation cannulae in the heart. Two devices are involved, the first for an atrial or venous return cannula and the second for an aortic perfusion cannula. These allow quick easy cannulation which is very important in emergency surgery.     

Preliminary results of intermittent retrograde cerebral perfusion during proximal aortic arch surgery.

OBJECTIVE: Continuous retrograde cerebral perfusion during aortic arch surgery is associated with cerebral edema. In this report, we describe the clinical use of a new type of intermittent retrograde cerebral perfusion. SUBJECTS AND METHODS: Fourteen patients with a Stanford type A dissection were included in this study. With the usual method of retrograde cerebral perfusion, about 2,500 mL venous blood is drained from bicaval cannulae into a hard-shell reservoir, and oxygenated blood is perfused through the superior vena caval cannula. The flow rate is 300 mL/min. After about 15 min, retrograde perfusion is discontinued, and drainage from the bicaval cannulae is restarted. When a bloodless field is necessary, perfusion also is discontinued. RESULTS: Two to seven cycles of intermittent retrograde cerebral perfusion were administered (average, 3.1+/-0.4, mean+/-SD). The total retrograde perfusion time was 36.0+/-1.9 min which was equivalent to 74.8% of the circulatory arrest time. No patient developed edema of the upper body. The time to wake-up was 3 to 14 h (average, 6.5+/-1.0 h). No patient suffered any neurologic complications even though the time of circulatory arrest was greater than 60 min in four cases. Head magnetic resonance imaging or computed tomography was performed in 12 cases, and no evidence of hypoxic brain injury was detected. CONCLUSIONS: Our clinical experience using a moderate amount of intermittent retrograde cerebral perfusion is superior to continuous retrograde cerebral perfusion for protecting the brain during aortic arch surgery.     

A Newly Designed Arterial Monitoring/Perfusion Cannula for Cardiac Operations

A newly designed arterial monitoring and perfusion cannula for cardiopulmonary bypass eliminates the need for cannulation of a peripheral artery for pressure monitoring. The double-lumen cannula is designed as follows: the large central lumen (12 to 26F) acts as the arterial inflow conduit from the pump oxygenator, while a second, smaller lumen (18 gauge) constructed in the wall of the first cannula acts as the pressure-monitoring port and the source for blood sampling and drug infusion. This monitoring/perfusion cannula has been used successfully in more than 250 clinical patients in a variety of settings—total cardiopulmonary bypass, left heart bypass, and when multiple arterial inflow lines were necessary (as in aortic arch replacement). Use of this cannula is advantageous in the infant and pediatric patient or in the emergency setting, when insertion of a peripheral arterial line can be difficult. Used in conjunction with a Doppler system, the cannula provides accurate, dependable blood pressure monitoring.     

Differential perfusion: a new technique for isolated brain cooling during cardiopulmonary bypass

BACKGROUND: The purpose of this study was to determine the feasibility of differential perfusion of the aortic arch and descending aorta during cardiopulmonary bypass using a cannula designed for aortic segmentation. METHODS: Pigs weighing 57 kg (n = 8), underwent cardiopulmonary bypass using the dual lumen aortic cannula. An inflatable balloon separated proximal (aortic arch) and distal (descending aorta) ports. During differential perfusion, the aorta was segmented and the arch and descending aorta perfused differentially using parallel heat exchangers. Ability to independently control brain and body temperature, cardiopulmonary bypass flow rate and mean arterial blood pressure was determined. RESULTS: During differential perfusion cerebral hypothermia (27 degrees C) with systemic normothermia (38 degrees C) was established in 23 minutes. Independent control of arch and descending aortic flow and mean arterial blood pressure was possible. Analysis of internal jugular venous O2 saturation data indicated an increase in the ratio of cerebral O2 supply to demand during differential perfusion. CONCLUSIONS: A cannulation system segmenting the aorta allows independent control of cerebral and systemic perfusion. This device could provide significant cerebral protection while maintaining the advantages of warm systemic cardiopulmonary bypass temperatures.     

Simultaneous antegrade/retrograde normothermic perfusion with blood (beating heart) for aortic root replacement in acute type-a dissection of the aorta

A new technique of myocardial protection was utilized in performing surgery for acute type-A dissection involving the aortic valve, requiring replacement of the root. Simultaneous antegrade and retrograde perfusion of the heart with normothermic blood at high flows allows for safe and precise surgery, without concerns for the period of aortic clamping, since ischemia is eliminated altogether.     

Redo valve surgery with on-pump beating heart technique

AIM: Reoperations have become of increasing frequency in the last four decades. Redo surgery is more complex than primary surgery and is associated with higher mortality and morbidity. We present our immediate and mid-term results of mitral and aortic prosthetic valve replacement undertaken with beating heart technique. METHODS: The prospective study included 26 consecutive redo valve surgery patients who underwent valve re-replacement. The operation was carried out on a beating heart using normothermic bypass without cross-clamping the aorta for mitral valve surgery and retrograde coronary sinus normothermic noncardioplegic blood perfusion during cross-clamping the aorta for aortic valve procedures. RESULTS: Twenty-six patients (mean age 50+/-15 years) underwent reoperation with beating heart technique. Twenty (76.9%) mitral prosthetic replacements, 4 (15.4%) aortic prosthetic replacements, and 2 (7.7%) double valve replacements were achieved. Fourteen patients (53.8%) were operated for prosthetic valve dysfunction. Eighteen patients (69.2%) were in NYHA class III or IV preoperatively. Mean bypass time was 85+/-30 min. Mean duration of ventilation was 13.6+/-6 h, mean intensive unit stay was 2.8+/-6.4 days, and mean hospital stay was 8.3+/-7.2 days. Two (7.7%) patients required high dose inotropic support and in one patient (3.8%) intra-aortic balloon support was required. Pulmonary complication occurred in 1 patient (3.8%), low cardiac output in 1 patient (3.8%), and re-exploration for bleeding in 2 patients (7.7%). Operative mortality was not observed. CONCLUSION: Normothermic on-pump beating heart valve replacement offers a safe alternative to cardioplegic arrest in high-risk group. Complication rates are low and perioperative mortality is lower than with conventional surgery. Beating heart technique has the advantage of maintaining physiologic condition of the heart throughout the procedure.