Clinically diagnosed nonocclusive mesenteric ischemia after cardiopulmonary bypass: retrospective study.

This retrospective study evaluates our experience with clinically diagnosed nonocclusive mesenteric ischemia after cardiopulmonary bypass. Twenty-three of 3,600 consecutive patients suffered from splanchnic malperfusion. Symptoms developed between day 2 and 6 postoperatively in 18 of 23 patients. Four of 23 patients had no abdominal symptoms. Laboratory evaluation revealed significantly higher serum lactate and creatine phosphokinase levels in the 18 symptomatic patients compared with those of a control group. Arteriography was performed in 20 cases and revealed nonocclusive splanchnic hypoperfusion. Risk factors for development of mesenteric ischemia include arrhythmias and low cardiac output. Patients with angiographically proven nonocclusive mesenteric ischemia were treated with intra-arterial bolus injection and subsequent intra-arterial infusion of tolazoline combined with heparin sodium. The overall mortality rate was 30% (7 of 23). Infusion therapy with tolazoline and heparin seems to be a successful treatment modality for clinically diagnosed mesenteric ischemia.

Simultaneous surgical revascularization and angiogenic gene therapy in diffuse coronary artery disease.

OBJECTIVE: The cytokine vascular endothelial growth factor (VEGF) is capable of triggering angiogenesis and at higher concentrations vasculogenesis. We report on a pilot study where VEGF-DNA as an additional therapy to coronary artery bypass grafting was injected into the myocardium in 24 patients (pts) with proximal coronary artery stenosis and diffuse peripheral disease. One region of the myocardium with proven ischemia remained unsupplied after surgery because the respective epicardial coronary artery was not graftable. METHODS AND RESULTS: Plasmid DNA encoding for the 165- and 167-amino acid isoform of the human VEGF genes was injected directly into the myocardium, not amenable to surgical revascularization at a dosage of 1000 microg each, using a standardized protocol. A (99m)Tc-sestamibi-SPECT at rest performed 7 days prior to the operation, had shown decreased marker activity in the region of interest. Controls were made 1 week and 80-100 days postoperatively. Transmural scarring was ruled out intraoperatively. Coronary and left ventricular angiographies were performed preoperatively and 3 months postsurgery, respectively. One or more of the following angiographic items were found in 16/24 patients postoperatively. (1) Improvement of regional left ventricular function at the VEGF treated myocardial sector (5/24 pts). (2) Newly visible vessels considered as collaterals (8/24 pts). (3) Earlier filling of parent vessels (6/24 pts). (4) An increase in diameter of preoperatively existing collateral vessels (7/24). An increased perfusion at rest in the region of gene application was detected in 3/24 patients by early postoperative (99m)Tc-sestamibi-SPECT investigation. In six additional cases, local perfusion increased markedly until the late examination. No perioperative myocardial infarctions and no signs of inflammation were observed. Newly developed abnormal vasculature was not detected in any patient. CONCLUSIONS: Direct intramyocardial administration of VEGF(165)-DNA and VEGF(167)-DNA may result occasionally in an enhancement of collateral vascularization in regions with diffuse peripheral coronary artery disease not surgically amenable. During midterm follow-up no adverse effects of VEGF-DNA application are observed so far. The very slight midterm improvements caused us to stop further VEGF-DNA application and, in our opinion, do not justify a prospective, and randomized study with a control group.

Cardiodynamic effects of dopamine and dobutamine.

On 11 patients undergoing coronary surgery, at the end of the surgical intervention, the inotropic responses to 0.4 and 0.8 microgram x kg-1 x min-1 dopamine and dobutamine given via the aorto-coronary bypass directly into the coronary artery were compared. These dosages correspond to ones 10 times greater applied intravenously. The measurements were made using needle force probes which were implanted into the myocardial offstream area in the left ventricular wall. Bypass flow was measured simultaneously by an electromagnetic flow probe. There is a significant increase in coronary bypass flow induced by both rates of 0.4 and 0.8 microgram x kg-1 x min-1 dobutamine, but there was no significant effect on bypass flow induced by dopamine. Developed myocardial force is raised more by dobutamine medication than by dopamine. However, the rate of contraction increases significantly and relaxation is significantly accelerated by dopamine at both dosages. A significant increase in rate of contraction and relaxation was only induced by the higher dosage of 0.8 microgram x kg-1 x min-1 dobutamine.

Endoscopic ultrasonography of the mediastinum in the diagnosis of bronchial carcinoma.

Thoracic computed tomography (CT) is an essential component in the preoperative staging of bronchial carcinomas as is mediastinoscopy (MSC) in cases of mediastinal lymphoma. It is known that endoscopic ultrasonography (EUS), as a new diagnostic procedure, can predict lymph-node involvement in cases of tumors in the upper gastrointestinal tract with an 80% probability. In a prospective study, we examined whether EUS could be used to ascertain the presence of mediastinal lymph nodes in cases of bronchial carcinoma. Since 1990, therefore, 32 patients with operable non-small-cell bronchial carcinoma have been examined with an Olympus-Aloka EU-M2 or EU-M3 (frequency 7.5 and 12 MHz) in addition to routine diagnostics. The graded cross-sections of lymph-node dissections obtained during subsequent surgery served as evidence as to the true or false prognosis of the lymph-node status. Endoscopic ultrasonography identifies the presence and estimates the size of subcarinal, tracheobronchial, paraortal and paraesophageal lymph nodes better than computed tomography. Lymph nodes lying behind organs containing air (pretracheal lymph nodes) cannot be identified by ultrasonography. Lymph-node involvement was correctly identified by EUS in 72% of the cases, and the specificity was 86%. The poor sensitivity, at 67%, is explained by the high proportion (37%) of patients with anthracosilicosis, as the latter produces the same echo pattern as malignant infiltration. In 47% of all the cases, CT showed enlarged mediastinal lymph nodes which were not actually infiltrated in 67%. Of these lymph nodes, 33% could be classified as definitely free of metastases on the strength of their echo pattern, the rest were inflamed or really infiltrated by metastases.(ABSTRACT TRUNCATED AT 250 WORDS)

Quantitative assessment of the effects of 'inodilators' on the myocardium in patients without primary cardiac insufficiency after coronary surgery: Part II--Enoximone.

Twelve patients undergoing routine coronary artery surgery received a bolus injection of 1.5 mg/kg enoximone between 8 and 18 hours and again between 18 and 48 hours after operation. No patient showed clinically manifest myocardial heart failure. The haemodynamic and cardiodynamic response to enoximone was quantified over a 30 minutes period following injection. Local myocardial developed force increased by 24 +/- 7% after the first and by 12 +/- 6% after the second injection. The rate of myocardial contraction increased by 50 +/- 14% and 15 +/- 10%, respectively, and relaxation increased by 35 +/- 14% and 22 +/- 19%. There was a decrease in total peripheral resistance of 38.8 and 42.9%, and an increase in heart rate of 11 and 15%. The mean arterial pressure showed small reductions from 73 (+/- 3.7) to 67 (+/- 2.6) mmHg for the first dose and from 83 (+/- 3.1) to 78.4 (+/- 2.8) mmHg for the second. Central venous and pulmonary artery pressures were essentially unaltered. The substantial positive inotropic effect of enoximone has been shown to match its peripheral vasodilatory activity, so that in the normovolaemic patient there is a clinically insignificant small fall in mean arterial pressure.

Quantitative assessment of the effects of 'inodilators' on the myocardium in patients without primary cardiac insufficiency after coronary surgery: Part I--Amrinone.

The positive inotropic and peripheral vasodilating effect of amrinone has been measured in 20 patients without manifest cardiac insufficiency during the early (8-18 h postoperative) and late (18-48 h postoperative) recovery phase after coronary surgery. On conclusion of the surgical intervention first the aortocoronary bypass flow was compared during dobutamine and amrinone administration. It increased by 88% with amrinone and by 19% with dobutamine. Then a needle force probe was implanted in the myocardium. Directly measured local myocardial force increased not significantly by 3.5% after the first and by 5.1% after the second bolus injection of 2 mg/kg amrinone. The rate of myocardial contraction increased by 18.7% and 12%. The rate of relaxation decreased by 5.3% after the first and increased by 15% after the second injection. Mean pulmonary arterial pressure fell from 18.5 to 15.5 mmHg and from 19.7 to 17 mmHg. Cardiac output increased by 23% after the first and by 20% after the second injection. Heart rate rose from 88 to 99 bpm and from 86 to 94 bpm. Total peripheral resistance fell from 1,035 to 706 dyn*s*cm-5 and from 1,036 to 819 dyn*s*cm-5. The systolic arterial pressure fell from 132 to 116 mmHg after the first injection and did not change after the second injection. Amrinone was found to be a powerful peripheral vasodilator with a mild positive inotropic action. The variations in the effects between the early and late recovery phases mainly reflect a progressive haemodynamic stabilization with a decreasing tendency toward hypotensive disregulation. Careful consideration has to be paid to a properly balanced filling of the vascular system before administering amrinone.

[Comparison of new cardiac agents using differential therapeutic criteria]. / Vergleich neuer Kardiaka nach differentialtherapeutischen Kriterien.

Positive inotropism, reduction in preload, and reduction in afterload induced by any cardiacum are not exactly quantified in humans, nor are the patients classified as to their respective requirements. Also, any of these drug activities change with the patient's instantaneous cardiac and hemodynamic functional state. One reason for incomplete knowledge is a shortage of methods which allow to assess the inotropic state of the myocardium. In 17 patients, age range 56-76 years (two females, 15 male), undergoing routine coronary surgery, informed consent was obtained for implantation of a needle transducer for measurement of wall force. At the end of coronary surgery, developed myocardial force and aorto-coronary bypass flow were measured electromagnetically. After control measurements, 0.03, 0.06 and 0.1 mg/kg enoximone were injected slowly (3 min per dose) into the aorto-coronary bypass. Eight to 18 h after surgery, and again 18-48 h after surgery, the following measurements were made, first as a control, and then after 1.5 mg/kg enoximone i.v.: aortic pressure (AoP), central venous pressure (CVP) and pulmonary artery pressure (PAP), cardiac output (CO), and heart rate (HR). Peripheral vascular resistance (TPR) was calculated. Developed force and its derivatives were recorded continuously. Immediately after recovery from cardioplegia a 0.19 mg/kg dose of enoximone injected over 9 min into the aorto-coronary bypass induced an increase in bypass flow of 64 +/- 30%. Mean arterial pressure (MAP) showed a fall 5 min after enoximon injection on both occasions. The values were 73 (+/- 3.7) to 67 (+/- 2.6) mmHg, and 83 (+/- 3.1) to 78 (+/- 2.8) mmHg, respectively. The increase obtained in cardiac output (CO) 6.0 (+/- 0.4) to 7.4 (+/- 0.7) l.min-1, and 6.2 (+/- 0.7) to 8.5 (+/- 1.3) l.min-1 was significant at 5 min and remained so at 30 min on both occasions.(ABSTRACT TRUNCATED AT 250 WORDS)

Epicardial coronary artery imaging.

Intraoperative high-frequency echocardiography with a 12-MHz linear scanner is a diagnostic tool for imaging coronary morphology. This method was used in 630 vascular sections in 112 operations. The vessel diameter (80%), the absence of stenoses (77%), the condition of the vessel wall (39%), and the localization of occlusions (14%) were examined. Fifty vessels not visible to the eye (8%) could be echocardiographically imaged. Anastomoses were examined 45 times (7%). By using high-frequency echocardiography, intraoperative decisions could be acted upon immediately in 46 operations (41%).

Intraoperative evaluation of coronary anatomy.

Intraoperative evaluation of coronary anatomy without arteriotomy is possible with the aid of high-frequency echocardiography (HFE). The 12 MHz linear scanner can image the coronary arteries with good resolution in the transverse section and the longitudinal course. Indications are the visualization of coronary vessels, localization of stenoses and occlusions, the measurement of vessels and stenoses and the evaluation of anastomoses.

Intraoperative use of high-frequency echocardiography for imaging the coronary arteries.

Until today, a routinely applicable method is not available for intraoperative imaging of the coronary vessels. Our experience with the first 23 patients is discussed to show whether high-frequency echocardiography (HFE) is able to close this gap and to image the coronary arteries intraoperatively in a manner which can be evaluated. After thoracotomy and connecting the heart-lung machine as well as insertion of a transatrial left ventricular vent, ultrasonography was carried out with a 12 MHz linear scanner with a water prerun in the LAD in all cases, and also in the RCA and circumflex branch in 12 cases using sterile ultrasound gel on the fibrillating heart. The results proved that the method is able to image the coronary arteries with good resolution in the transverse section and in the longitudinal course. HFE can be used in particular to locate the intramyocardial course of coronary vessels and in reoperations, for localization of stenoses and occlusions, for determination of optimal sites for anastomoses, for measuring of vessel diameter and degree of stenosis, and for imaging of anastomoses. It will be possible in the future to image and to check intraoperative dilatation and laser angioplasty with HFE.

Successful treatment of tumor embolism of a hypernephroma with complete occlusion of the left pulmonary artery.

A tumor embolism with occlusion of the left pulmonary artery was the first manifestation of a hypernephroma. After angiographic diagnosis, embolectomy was performed successfully using the heart-lung-machine. Four days later, nephrectomy followed. In the meantime, the patient has experienced a period of 3 years free of symptoms and metastases.