Removal of the stylet from the tracheal tube: effect of lubrication.

We compared the work needed to retract a non-lubricated and a lubricated stylet from a tracheal tube over 24 h. Stylets were lubricated with sterile water, silicone fluid, lidocaine spray, lidocaine gel, MedPro(®) lubricating gel or Lacri-Lube(®). The mean (SD) work in joules needed to retract the stylet by 5 cm from the tracheal tube was recorded immediately (time 0), at 5 and 30 min and at 1, 3 and 24 h. At time 0 lubrication with sterile water (0.53 (0.09); p = 0.001), silicone fluid (0.43 (0.10); p < 0.001), lidocaine gel (0.60 (0.15); p = 0.01) and MedPro gel (0.57 (0.07); p = 0.005), were better than no lubrication (0.94 (0.28)). Where a tracheal tube is pre-loaded with a stylet for use at an indeterminate time, silicone fluid was the best choice of lubricant as it performed consistently well up to 24 h. At 24 h only silicone fluid (0.49 (0.01)) outperformed no lubrication (0.77 (0.24); p = 0.04).

Involvement of cyclooxygenase 2 and prostagladin E(2) in the effects of insulin on gastric emptying in male rats.

Delayed gastric emptying in patients with both type 1 and type 2 diabetes mellitus (DM) occurs in approximately 50% of these patients. However, the role and the action mechanism of insulin on gastrointestinal (GI) motility are still unclear. The purpose of the present study was to investigate the involvement of cyclooxygenase-2 (COX-2) and prostaglandin E(2) in the effects of insulin on gastric emptying in male rats. The normal and streptozotocin (STZ)-pretreated rats were injected intraperitoneally with or without insulin, atropine and specific muscarinic receptor antagonists before examination of measurement of gastric emptying, spontaneous contractile activity of smooth muscle strips, plasma cholecystokinin (CCK), and prostaglandin E(2) (PGE(2)) analysis. Protein expression of COX-2 and insulin receptors (IRs) were analyzed by the technique of western blot. Acute different doses of insulin accelerated gastric emptying. Atropine interrupted the insulin effect on gastric emptying, and muscarnic M1/M3 receptor antagonists interrupted the insulin-reversed gastric emptying in normal and DM rats. Besides, we observed the expression of (IRs) in GI and found that IR was changed under the insulin and DM treatment, and was also different between STZ-pretreated rats and hyperglycemic rats. Expression of COX-2 in stomach was decreased in DM rats but restored by insulin. The COX inhibitor, indomethacin, decreased the gastric emptying which was induced or reversed by insulin in normal and DM rats, respectively. PGE(2) production in stomach corresponded to the COX-2 expression. The contraction of GI smooth muscle stimulated by PGE(2) was increased in insulin-pretreated normal and DM rats. We conclude that insulin changed the expression of IRs in stomach in DM rats. The delayed GI motility in diabetes was at least in part due to the COX-2 and PGE(2) pathway which associated with decreasing COX-2 and diminishing PGE(2) production in stomach. The attenuation of PGE(2) production was employed for the index of the reduction of smooth muscle contraction in stomach in diabetes. Insulin stimulated the smooth muscle contraction through the IRs and COX-2 expression plus PGE(2) production in rat stomach as well as reversed the delayed gastric emptying via the nervous actions of muscarinic M1 and M3 receptors in DM rats.

Outcome of off-pump coronary artery bypass in renal dialysis patients.

BACKGROUND: Renal dialysis patients are a subgroup at major operative risk when undergoing coronary artery bypass grafting (CABG). Even though CABG without cardiopulmonary bypass (CPB) has decreased the surgical risk and provided good short-term results, the long-term survival seems uncertain. We report here on the long-term outcome of CABG without CPB in renal dialysis patients. METHODS: From 1998 to 2002, 44 renal dialysis patients underwent elective CABG without CPB, including 17 minimally invasive direct coronary artery bypass (MIDCAB) and 27 off-pump CABG (OPCAB) procedures. There were 5 one-vessel, 12 two-vessel and 27 multi-vessel coronary artery disease patients, who mainly had left internal thoracic artery (LITA) to left anterior descending coronary artery (LAD) grafting with an additional saphenous vein graft to non-LAD coronaries. RESULTS: All 44 patients were followed up for 44.4 +/- 31.2 months. Three (6.8 %) surgical deaths within 30 days occurred and 25 late mortalities happened over a period of 2 - 79 months. The 5-year cumulative rate of total survival is 38.2 % and the freedom from cardiac death is 70.9 %. Using hazard analysis, old age (> 60 years) and incomplete coronary revascularization was found to significantly affect the total survival. CONCLUSIONS: CABG without CPB provided an acceptable surgical mortality and morbidity. The high incidence of non-cardiac death associated with dialysis complications had an adverse impact on the overall outcome. The LITA bypass operation method combined with intensive care for dialysis complications would hopefully fulfill the goal to improve the short- and long-term results in this subgroup.

Intracavitary metastatic hepatocellular carcinoma of the right ventricle.

We report a rare case of direct intracavitary metastasis of a hepatocellular carcinoma (HCC) to the right ventricle (RV) without intravascular involvement. A 65-year-old female, with a history of HCC and partial right hepatectomy, developed symptoms of congestive heart failure. Echocardiography revealed a large tumor in the RV with extension to the outflow tract. Palliative excision of the cardiac tumor under cardiopulmonary bypass and cardioplegic arrest was performed due to severe hemodynamic compromise. The final pathology report disclosed metastatic HCC. Tumor recurrence in the RV was noted 2 months later and the patient succumbed to the disease.

Involvement of cholecystokinin receptor in the inhibition of gastrointestinal motility by estradiol in ovariectomized rats.

BACKGROUND: The effects of estradiol benzoate (EB) on gastric emptying, gastrointestinal transit and plasma levels of cholecystokinin (CCK) were studied in ovariectomized rats. METHODS: Gastrointestinal motility was assessed in rats 15 min after intragastric instillation of a test meal containing charcoal and Na2 51CrO4. Gastric emptying was determined by measuring the amount of radiolabeled chromium contained in the small intestine as a percentage of the initial amount received. Gastrointestinal transit was evaluated by calculating the geometric center of distribution of the radiolabeled marker. Blood samples were collected for E2 and CCK radioimmunoassay. RESULTS: After treatment of EB (4-25 microg/kg), gastric emptying and gastrointestinal transit were inhibited, whereas plasma concentrations of E2 and CCK were increased in a dose-dependent manner. The selective CCK(A) receptor antagonists, devazepide and lorglumide, effectively attenuated the EB-induced inhibition of gastric emptying and gastrointestinal transit. L-365,260, a selective CCK(B) receptor antagonist, did not alter the EB-induced inhibition of gastric emptying and gastrointestinal transit. CONCLUSIONS: The results suggest that EB inhibits gastric emptying and gastrointestinal transit in ovariectomized rats via a mechanism involving CCK stimulation and CCK(A) receptor activation.

A minimal transverse incision with low median sternotomy for pediatric congenital heart surgery.

OBJECTIVES: Median sternotomy is the incision of choice for most cardiac surgical procedures, but the full-length vertical skin incision generally leaves an unsightly scar. In certain patients undergoing short, low-risk procedures, cosmetic considerations are of relatively greater importance. METHODS: A minimal transverse curvilinear skin incision with low median sternotomy is described which gives adequate exposure for selected open-heart procedures. Since September 1997, this approach has been used in 22 pediatric patients undergoing open-heart surgery including five cases of Fallot's tetralogy. We also compared the operation time and result with other approaches. RESULTS: Using this modified method, the exposure of the heart was good enough, and there were no difficulties in cannulating the ascending aorta for cardiopulmonary bypass. Although it took a longer time to close the wound, the operation time was similar to the standard approach. The small transverse wound was not visible under conventional clothes. CONCLUSIONS: A minimal transverse incision with low median sternotomy provides an alternative approach for small wound open-heart surgery in patients with a simple congenital cardiac defect. It is technically feasible and has a good cosmetic result.

Role of histamine in aggravation of gastric acid back-diffusion and vascular permeability in septic rats.

The aim of the present study was to investigate the role of histamine in aggravation of gastric acid back-diffusion and vascular permeability in lipopolysaccharide (LPS)-induced septic rats. Male specific pyrogen-free Wistar rats were deprived food for 24 h before the experiment. Intravenous LPS (3 mg/kg dissolved in sterilized saline) was given to rats 12 h after food removal. Control rats received sterilized saline only. Under diethylether-anesthesia, the pylorus and esophageal sphincters of rats were ligated. Vagotomy also was performed. The stomachs were then irrigated for 3 h with physiological acid solutions containing 0-150 mM HCl plus adequate amount of NaCl. Increases in various ulcerogenic parameters, such as gastric acid back-diffusion, mucosal histamine concentration, luminal hemoglobin (Hb) content and stomach ulcer, were dependent on the concentration of acid solutions irrigated in stomachs of those LPS rats. Gastric vascular permeability also was increased in an acid concentration-related manner. In those LPS rats, high correlation was found between extents of acid back-diffusion and mucosal ulceration. Increased vascular permeability also closely related to the luminal Hb content. Moreover, these ulcerogenic parameters were dose-dependently ameliorated by intraperitoneal ketotifen and ranitidine. Diamine oxidase also was effective in inhibition, but exogenous histamine on the contrary, produced exacerbation of these ulcerogenic parameters. In conclusion, histamine plays a pivotal role in modulating gastric acid back-diffusion and vascular permeability that are greatly associated with hemorrhagic ulcer in septic rats.

Intravenous amiodarone for prevention of atrial fibrillation after coronary artery bypass grafting.

BACKGROUND: Atrial fibrillation occurs in 10% to 40% of patients who undergo coronary artery bypass grafting. This prospective study assesses the safety and efficacy of low-dose intravenous amiodarone in the prevention of atrial fibrillation after coronary artery bypass grafting. METHODS: One hundred forty patients were randomly divided into two groups: an amiodarone group (n = 74) receiving intravenous amiadarone in a loading dose of 150 mg and maintenance dose of 0.4 mg x kg(-1) x h(-1) for 3 days before and 5 days after operation and a control group (n = 76) receiving matching infusions of 5% glucose solution. RESULTS: Atrial fibrillation occurred in 9 (12%) of the amiodarone group patients and in 26 (34%) of the control group patients during hospitalization (p < 0.01). The maximum ventricular rate during atrial fibrillation was significantly slower in the amiodarone group (107 +/- 21) than in the control group (138 +/- 24 beats per minute, p < 0.01). The duration of atrial fibrillation in the amiodarone group (1.1 +/- 1.2 hours) was significantly shorter than that in the control group (3.2 +/- 1.3 hours, p = 0.01). The two groups had no significant differences in incidence of major morbidity (8 of 74 versus 8 of 76 in amiodarone and control groups, respectively) or mortality (4 of 74 versus 5 of 76). However, the control group had significantly longer intensive care unit stays (132 +/- 24 versus 111 +/- 19 hours, p < 0.01). CONCLUSIONS: Perioperative low-dose intravenous amiodarone significantly reduces the incidence, ventricular rate, and duration of atrial fibrillation after coronary artery bypass grafting. Furthermore, low-dose intravenous amiodarone is well tolerated and does not increase the risk of intraoperative or postoperative complications.

Gastric mucosal damage induced by arecoline seizure in rats.

In an attempt to know the relation of seizure and gastric mucosal damage, we challenged arecoline (ACL) centrally to induce seizure and investigated gastric hemorrhagic injury in acid-irrigated stomachs of rats. The protective effects of several drugs also were evaluated. After deprivation of food for 24 h, rats were received laparotomy under diethylether-anesthesia. Both pylorus sphincters and carotid esophagus were ligated. The forestomach was equipped with a cannula for gastric irrigation. After recovery from anesthesia (approximately 1 h), the stomach was irrigated for 2 h with an acid solution containing 100 mM HCl and 54 mM NaCl or the same volume of normal saline. Intracerebroventricular (i.c.v.) ACL (0, 1, 3 or 10 mg/kg dissolved in 10 microl of CSF) was challenged to rats immediately after gastric irrigation. The seizure in rats was produced by ACL in a dose-related manner. The ulcerogenic parameters such as decrease of gastric mucosal glutathione levels and increase of histamine concentrations and lipid peroxide generations as well as the raise of luminal hemoglobin contents and exacerbated mucosal lesions were obtained depending on the doses of ACL challenged. These ulcerogenic parameters produced in ACL (10 mg/kg, i.c.v.) seizure rats were markedly ameliorated by gastric vagotomy or central anticholinergics. Intraperitoneal ketotifen, zinc sulfate, diphenhydramine or cimetidine also produced significant (p<0.05) inhibitions of these ulcerogenic parameters in ACL seizure rats. In conclusion, central ACL seizure may produce gastric oxidative stress and hemorrhagic lesions via vagal nervous activation and histamine release in acid-irrigated stomachs of rats.

Importance of histamine, glutathione and oxyradicals in modulating gastric haemorrhagic ulcer in septic rats.

1. The ulcerogenesis of gastric haemorrhagic damage during sepsis is unclear. The present study first proposes that gastric haemorrhagic ulcer is modulated by mucosal glutathione, histamine and oxyradicals in lipopolysaccharide (LPS)-induced sepsis in rats. The protective effects of several drugs on the ulcerogenic parameters also were evaluated. 2. Male specific pyrogen-free Wistar rats were deprived of food for 24 h. For the induction of sepsis, intravenous LPS (0, 1, 3 or 10 mg/kg in 1 mL sterilized normal saline) was challenged to rats 12 h after withdrawal of food. Rat stomachs were vagotomized, followed by irrigation for 3 h with normal saline or a physiological acid solution containing 100 mmol/L HCI and 54 mmol/L NaCl. 3. The aggravation of gastric ulcerogenic parameters, such as gastric acid back-diffusion, luminal haemoglobin content, mucosal lipid peroxide production, histamine concentration, as well as lowered concentrations of defensive substances, including mucosal glutathione, were dependent on the doses of LPS used for challenge. A high correlation was observed between mucosal histamine release and lipid peroxide production in LPS rats. 4. The ulcerogenic parameters obtained in LPS (3 mg/kg, i.v.) rats were potently attenuated by diamine oxidase, ketotifen and zinc sulphate. 5. Several oxyradical scavengers, including glutathione, dimethylsulphoxide and allopurinol, also were effective in inhibiting haemorrhagic ulcer. 6. In conclusion, gastric mucosal histamine release and oxyradical generation play pivotal roles in the formation of haemorrhagic ulcers in septic rats.

Effect of verapamil on long-term tachycardia-induced atrial electrical remodeling.

BACKGROUND: The effect of verapamil on long-term tachycardia-induced atrial electrical remodeling has not been reported. METHODS AND RESULTS: Forty-eight dogs were randomly divided into verapamil and control groups. The dogs in the verapamil group received verapamil 120 mg every day, those in the control group did not receive verapamil. Atrial effective refractory period (AERP), inducibility of atrial fibrillation (AF), and duration of AF were assessed before and after complete atrioventricular junction ablation with 1-day, 1-week, or 6-week rapid atrial pacing (780 bpm). AERP shortening, AERP dispersion, AERP maladaptation, and inducibility of AF after 1-day pacing was significantly attenuated by verapamil. However, verapamil did not have any significant effect on these parameters in the dogs with 1-week or 6-week pacing. Verapamil did not have any significant effect on the conduction velocity in the dogs with 1-day, 1-week, or 6-week pacing. Before rapid atrial pacing, verapamil significantly prolonged the duration of AF. In the dogs with 1-day pacing, the duration of AF measured immediately after termination of pacing was similar between the control and verapamil groups. However, in the dogs with 1-week or 6-week pacing, the duration of AF after pacing was significantly longer in the verapamil group. CONCLUSIONS: Verapamil cannot prevent long-term (1 and 6 weeks, respectively) tachycardia-induced changes of atrial electrophysiological properties. Furthermore, verapamil increases the duration of AF in the dogs either before or after long-term rapid atrial pacing.

Influence of aortopulmonary rotation on the anomalous coronary artery pattern in tetralogy of fallot.

Three main patterns of aortic sinus rotation were defined on 517 lateral angiograms of tetralogy of Fallot with 14 cases of anomalous coronary artery pattern occurring only in patients with a right anterior or right lateral aorta. The significant dependence of coronary artery types on the aortic sinus pattern made it possible to predict the predisposing coronary artery pattern in tetralogy of Fallot based on the aortic sinus pattern.

Change of atrial refractory period after short duration of rapid atrial pacing: regional differences and possible mechanisms.

It is unknown whether there are regional differences in the change of atrial effective refractory period (ERP) after a short duration of rapid atrial pacing. Furthermore, the effects of calcium channel and potassium channel on this phenomenon have not been extensively investigated. In opened-chest dogs, the endocardial monophasic action potential duration at 90% repolarization (APD90) from the right atrial appendage, and ERP from seven atrial sites were measured before and after rapid atrial pacing at 800 beats/min for 30 minutes. Both atrial ERP and APD90 significantly shortened after rapid atrial pacing. The postpacing atrial ERP and APD90 shortening persisted for 119 +/- 3 and 123 +/- 4 seconds after cessation of pacing, respectively. There was no significant difference in the magnitude or recovery course of atrial ERP shortening after pacing among the seven atrial sites. Pretreatment with nicorandil and d-sotalol had no effects on the magnitude or recovery course of atrial ERP shortening after pacing. However, the degree of ERP and APD90 shortening after pacing was significantly attenuated in the verapamil and ryanodine groups; furthermore, the recovery of ERP and APD90 after cessation of pacing was faster in the two groups. In conclusion, shortening of atrial ERP induced by short-duration rapid atrial pacing was uniform in both atria. Both the adenosine triphosphatase (ATP) dependent potassium current and rapid component of the delayed rectifier did not significantly influence this phenomenon, but both the verapamil and ryanodine could significantly attenuate the degree of atrial ERP and APD90 shortening.

The role of P wave in prediction of atrial fibrillation after coronary artery surgery.

Atrial fibrillation (AF) is a common arrhythmia after coronary artery bypass surgery (CABG). The purpose of this study was to determine the role of P wave duration, amplitude and dispersion in the prediction of AF after CABG. This study included 120 patients undergoing elective CABG. Clinical characteristics, 12-lead electrocardiogram (ECG), echocardiogram and coronary angiogram were obtained in all patients. We measured P wave duration, amplitude and dispersion from 12-lead ECG in each patient. After CABG, all patients were continuously monitored for AF attacks in the intensive care unit and ordinary ward. Our results showed that age greater than 60 years was the strongest predictor of postoperative AF (p<0.01), with a 3.7-fold greater likelihood of developing postoperative AF compared to ages less than 60 years. Gender was another independent predictor of postoperative AF, with men being 3.0 times more likely to develop postoperative AF compared to women (p = 0.03). The presence of prolonged P wave duration (> or =100 ms in lead II) was also an independent predictor (p = 0.04), with 2.9-fold greater risk of developing postoperative AF compared to a P wave duration of less than 100 ms. The P wave dispersion was similar between patients with and without postoperative AF (29+/-15 vs. 33+/-15 mm, p = NS). In conclusion, old age, male gender and prolonged P wave duration were independent predictors of AF after CABG. However, P wave dispersion and amplitude did not provide significant information in the prediction of postoperative AF.

Circadian variation of paroxysmal supraventricular tachycardia.

BACKGROUND: Various clinical manifestations of cardiovascular diseases have a pattern of circadian variation. In this study, we investigated whether the onset and duration of paroxysmal supraventricular tachycardia (PSVT) has a circadian variation. METHODS AND RESULTS: In our analysis, we included 105 patients with 498 PSVT episodes. In this study, the onset of PSVT did not have a uniform distribution throughout the 24-h period. There were nearly equal peaks in the time periods from 8:00 to 9:00 AM, 12:00 to 1:00 PM, and 5:00 to 6:00 PM, with a trough at night. The duration of PSVT also did not show a uniform distribution throughout the 24-h period; it increased significantly during the daytime, with a peak between 1:00 and 2:00 PM, another peak between 6:00 and 7:00 PM, and a significant reduction at night. CONCLUSIONS: The onset and duration of PSVT showed a circadian variation. However, the time-oriented antiarrhythmic therapy for preventing PSVT needs further study.

Regional differences in the recovery course of tachycardia-induced changes of atrial electrophysiological properties.

BACKGROUND: Regional differences in recovery of tachycardia-induced changes of atrial electrophysiological properties have not been well studied. METHODS AND RESULTS: In the control group (5 dogs), atrial effective refractory period (AERP) and inducibility of atrial fibrillation (AF) were assessed before and every 4 hours for 48 hours after complete atrioventricular junction (AVJ) ablation with 8-week VVI pacing. In experimental group 1 (15 dogs), AERP and inducibility of AF were assessed before and after complete AVJ ablation with 8-week rapid right atrial (RA) pacing (780 bpm) and VVI pacing. In experimental group 2 (7 dogs), AERP and inducibility of AF were assessed before and after 8-week rapid left atrial (LA) pacing and VVI pacing. AERP and inducibility and duration of AF were obtained from 7 epicardial sites. In the control group, atrial electrophysiological properties obtained immediately and during 48-hour measurements after pacing did not show any change. In the 2 experimental groups, recovery of atrial electrophysiological properties included a progressive recovery of AERP shortening, recovery of AERP maladaptation, and decrease of duration and episodes of reinduced AF. However, recovery of shortening and maladaptation of AERP and inducibility of AF was slower at the LA than at the RA and Bachmann's bundle. CONCLUSIONS: The LA had a slower recovery of tachycardia-induced changes of atrial electrophysiological properties, and this might play a critical role in initiation of AF.

Protective effects of several amino acid-nutrients on gastric hemorrhagic erosions in acid-irrigated stomachs of septic rats.

Our previous report demonstrates that severe gastric mucosal damage is produced in lipopolysaccharide (LPS)-intoxicated rats. In the present study, we examined protective effects of several amino acids including taurine, phenylalanine and L-Arginine on gastric hemorrhagic erosions in acid-irrigated stomachs of LPS rats. The animals were deprived of food for 24 hr. Intravenous LPS (3 mg/kg) was challenged 12 hr after withdrawal of food. Gastric vagotomy was performed, followed by irrigation the stomachs for 3 hr with a physiological acid solution containing 100 mM HCl and 54 mM NaCl. The ulcerogenic parameters including increased gastric acid back-diffusion, mucosal histamine concentrations, lipid peroxide productions, luminal hemoglobin contents, stomach erosions and the lowered glutathione levels were markedly enhanced in LPS rat stomachs irrigated with acid solution. Both phenylalanine and taurine caused dose-dependent attenuations of these ulcerogenic parameters in LPS rats. L-arginine also was effective in inhibition. The inhibitory effect was restored by pretreatment of nitric oxide synthase inhibitors, such as N(G)-nitro-L-arginine-methyl ester or L-N(G)-(1-iminoethyl)-lysine. Furthermore, marked amelioration of hemorrhagic erosions in LPS rats was observed when a combination of these amino acid nutrients was used. The results provide evidence that these amino acid nutrients may ameliorate gastric hemorrhagic erosion via GSH synthesis stimulation, histamine cell membrane stabilization and antioxidant actions in LPS rat stomachs.

A method to reduce response times in prehospital care: the motorcycle experience.

This study compared the response times of a motorcycle and a standard ambulance in a congested urban emergency medical services (EMS) setting. The study was performed in Taipei, Taiwan, a densely populated urban area. A basic life support (BLS) motorcycle (without defibrillation capability) and an advanced life support (ALS) ambulance were based at three study hospitals and simultaneously dispatched when there was a perceived need for ALS ambulance transport. Over a 3-month period, prehospital personnel evaluated 307 medical and trauma emergencies. Time data were insufficient for analysis in 33 cases, leaving a study population of 274. Response times of the motorcycle and the ambulance were prospectively assessed and compared. During rush hours, the response times of the motorcycle and ambulance were 4.9+/-3.0 minutes and 6.3+/-3.4 minutes (P < .05), respectively, and in non-rush hours, 4.2+/-2.1 minutes and 5.1+/-2.5 minutes (P < .05), respectively. Using motorcycles to transport EMTs to the emergency scene significantly reduced response time compared with a standard ambulance in a congested urban setting. Large prospective studies are required to determine the impact on patient outcome of shorter EMS response times using motorcycles. EMS motorcycles appear feasible and deserve consideration to help expedite prehospital care in other systems in densely populated cities.

Cardiac troponin T, creatine kinase, and its isoform release after successful percutaneous transluminal coronary angioplasty with or without stenting.

BACKGROUND: Cardiac troponin T is a sensitive and specific marker for the detection of minor myocardial injury. However, it has been rarely used to monitor myocardial injury after coronary stenting. The purpose of the study was to measure troponin T after apparently successful percutaneous transluminal coronary angioplasty (PTCA) with or without coronary stenting and to compare its result with serum creatine kinase and its isoform, CKMB. METHODS: The incidence of cardiac troponin T elevation was compared with that of creatine kinase or CKMB in 120 consecutive patients with symptomatic ischemia undergoing visually successful PTCA with (n = 59) or without stenting (n = 61). Troponin T, creatine kinase, and CKMB were measured before, immediately after, and 18 to 24 hours after the procedures were performed. RESULTS: No patient had abnormal troponin T, creatine kinase, or CKMB levels before and immediately after the procedures. Moreover, no patient showed electrocardiographic evidence of myocardial infarction. Troponin T was elevated in 17 patients at 18 to 24 hours after coronary stenting and in eight patients after PTCA. Both creatine kinase and CKMB were elevated in five patients after coronary stenting and in three patients after PTCA. The frequency of abnormal troponin T levels was significantly higher than that of creatine kinase or CKMB after coronary interventions (21% vs 6.7%; p < 0.01), and it was significantly higher after stenting when compared with angioplasty alone (29% vs 13%; p < 0.05). Patients with abnormal troponin T levels were more likely to undergo repeat revascularization than those without (24% vs 6%; p < 0.01). CONCLUSION: Cardiac troponin T is more sensitive than creatine kinase and CKMB in detecting minor myocardial injury after coronary interventions. The incidence of troponin T release is higher in the patients undergoing stent implantation than in patients treated with angioplasty alone.