Search

The purpose of the study was to evaluate the effects of regular warm-up, and upper-body vibration (UBV), or UBV+ short warm-up on swimming performance in Masters Swimmers. Six women and 4 men, mean age 35 ± 9 years, active master swimmers volunteered to participate in the study. Participants were assigned to complete 1 of 3 warm-up types: regular, UBV-only, or UBV + short, rest for 3 minutes, and then completed a 50-yd (45.7 m) freestyle maximal performance time trial. The UBV treatment consisted of 5 minutes of upper-body vibration with a frequency of 22 Hz. Rating of perceived exertion (RPE) and heart rate (HR) were measured post warm-up and post 50-yd time trial. No significant mean differences (p = 0.56) were found among regular, UBV-only, or UBV + short warm-ups for 50-yd freestyle time (29.1 ± 3.36, 28.9 ± 3.39, and 29.1 ± 3.55 seconds, respectively). Individual data indicated that 40% (4/10) of the swimmers swam their fastest with UBV-only and 20% (2/10) with UBV + short warm-up compared to 40% (4/10) with regular warm-up. The RPE pre and post warm-ups did not differ significantly (p = 0.059 and p = 0.216, respectively). A significantly higher (p = 0.023) HR was observed after regular warm-up compared to UBV + short warm-up. Furthermore, HR post 50-yd after regular warm-up was significantly higher compared to UBV-only (p = 0.005) and UBV + short warm-up (p = 0.013). The findings of the present study indicate that UBV and UBV + short warm-up may be considered as addition or an alternative warm-up strategy to regular swimming warm-up, producing reduced cardio stress and perceived effort.

Objective: To assess the results of a new cardioversion service that used intravenous midazolam sedation with cardioversion performed with a biphasic defibrillator by an experienced doctor with a prior review of patients in a pre-cardioversion clinic., Methods: 368 consecutive patients who were treated under the new service over its first 12 months (group 1) were compared with 210 consecutive patients who attended under the old system during the preceding 12 months (group 2). Patients of group 2 had cardioversion under general anaesthesia by junior doctors with a monophasic defibrillator., Results: There were no anaesthetic or respiratory complications in group 1. Of the patients in group 1, 10.3% remembered the shocks, with only 3.5% considering them unpleasant. Cardioversion was successful in 94.6% of group 1 patients after a mean energy of 117 J compared with 81.4% (p < 0.0001) and a mean energy of 242 J (p < 0.0001) for group 2 patients. Cancellations on the day of the procedure were reduced from 24% in group 2 to 3.4% in group 1., Conclusions: The new service was found to be safe and more efficient. It has led to a large reduction in the waiting time for cardioversion.

The aim of this study was to assess the quality of angiograms obtained using 4 Fr catheters compared with 6 Fr catheters, the ease of use of the 4 Fr catheters, and the safety of patient mobilization 1 hr following 4 Fr angiography. Details of catheter performance and procedural details were recorded at the time of the angiogram. The angiographic images were scored on the quality and completeness of vessel opacification throughout systole and diastole. A total of 410 patients were recruited. There was no difference between 4 and 6 Fr for procedural variables. All angiograms were considered to be of diagnostic quality. The angiographic scores for the right coronary artery and left ventricular injections were no different between 4 and 6 Fr. However, the angiographic scores for the left anterior descending and circumflex arteries were lower with 4 than with 6 Fr (both P < 0.05). Patients who had 4 Fr angiography mobilized safely at 1 hr and reported significantly less discomfort and bruising than 6 Fr patients. Good-quality diagnostic coronary angiograms can be achieved using 4 Fr catheters with the advantage of earlier postprocedural mobilization and reduced discomfort and bruising for the patient., (Copyright 2001 Wiley-Liss, Inc.)

ReoPro (abciximab) is an extremely potent inhibitor of the glycoprotein IIb/IIIa receptor, the final common pathway of platelet activation and aggregation. Its main role is the maintenance of coronary patency after suboptimal results with coronary intervention. However, one of the complications of this treatment is excessive bleeding, a problem which may be compounded by a rare idiosyncratic thrombocytopenic reaction. A severe episode of thrombocytopenia in a 64 year old man is described; he was treated with ReoPro for a right coronary stenosis which had not been resolved by angioplasty. His platelet level dropped quickly and only improved after 20 units of platelets were given.

Objectives: We sought to determine whether 12,500 IU of unfractionated heparin given subcutaneously twice daily for 4 months after percutaneous transluminal coronary angioplasty beneficially influences the subsequent rate of angiographic restenosis and the incidence of clinical events., Background: Heparin has been shown to exhibit powerful antiproliferative effects against smooth muscle cells in several animal models., Methods: A randomized trial with blinded data analysis was undertaken to assess the effect of unfractionated subcutaneous heparin on angiographic restenosis after coronary angioplasty. After successful angioplasty, patients were randomized to receive no heparin or 12,500 IU of heparin given subcutaneously twice daily for 4 months. Quantitative coronary angiography was performed before angioplasty, immediately after angioplasty and at follow-up ("early" [before 4 months] or electively [at 4 months])., Results: The study group comprised 339 patients, 167 randomly assigned to receive heparin, 172 to receive no heparin. Repeat cardiac catheterization was performed in 90% of randomized patients. At early and elective restudy (mean 4.2 months), the mean +/- SD difference in minimal lumen diameter between the postangioplasty and follow-up measurement was -0.55 +/- 0.58 mm for the no heparin group and -0.43 +/- 0.59 mm for the heparin group (p = NS). Clinical events during the follow-up period did not differ significantly between groups: fatal myocardial infarction (1 patient in each group), coronary bypass grafting (5 patients in each group), repeat angioplasty (12 in the no heparin, 6 in the heparin group), angina at 4-month assessment (33% in the no heparin, 32% in the heparin group)., Conclusions: Long-term treatment with high dose subcutaneous heparin (12,500 IU twice daily) for 4 months did not favorably influence angiographic or clinical outcome after coronary angioplasty.

Stents rarely thrombose in the first 24 hours after implantation; secondly, heparin has some influence on the extrinsic pathway. Additionally, if too much heparin is present it interferes with the INR, and the half life of prothrombin suggests that the patient should be anticoagulated with heparin for up to 96 hours after starting warfarin. This is the evidence on which our standard protocol is based.

We have assessed bedside kits for monitoring the activated partial thromboplastin time and the activated clotting time by comparing them with laboratory activated partial thromboplastin time values. To determine the accuracy of anticoagulation we have concurrently measured the plasma heparin concentrations, and plasma prothrombin fragment F1 + 2 concentrations. Serial samples were taken from patients undergoing elective percutaneous transluminal coronary angioplasty (n = 14). Readings were taken pre-procedure, 30 min after administration of a heparin bolus (10,000 U) and 1, 2 and 3 h after commencement of a constant heparin infusion (15 U/kg/h) postprocedure. Activated partial thromboplastin time results obtained with the bedside kit compared reliably with laboratory values (r = 0.8), were rapidly available and were reflected by appropriate changes in prothrombin fragment F1 + 2 and heparin concentrations. However, the relationship between activated partial thromboplastin time values and activated clotting time was less precise (r = 0.59). Therefore, for routine and frequent monitoring of anticoagulation with heparin, a bedside activated partial thromboplastin time kit provides adequate control of therapy but in instances were particularly tight control of anticoagulation is required, use of prothrombin fragment F1 + 2 concentrations may be more appropriate.

There is evidence that intravenous nitrates which are frequently used in acute coronary syndromes may interfere with the anticoagulant effect of heparin. We compared the effect of two different nitrate preparations on the activated partial thromboplastin time (APTT), anti-thrombin III activity (AT III) and plasma heparin levels in patients (n = 50) undergoing routine percutaneous transluminal coronary angioplasty (PTCA) for stable angina. Patients were randomized to either: (1) intravenous heparin and nitroglycerin (GTN); or (2) intravenous heparin and isosorbide dinitrate. The APTT, plasma heparin concentration and AT III activity were measured before PTCA and at 2 and 4 hours after commencement of infusions. Both groups received identical doses of heparin. Group 1 patients received a constant dose of 16.6 micrograms/minute of GTN, and group 2 patients received 33.3 micrograms/minute of isosorbide dinitrate. At 4 hours the median APTT ratio was significantly lower in group 1 compared with group 2 (2.6 versus 4.5) (P < 0.05) as was the plasma heparin concentration (0.18 U/ml versus 0.32 U/ml (P < 0.05). However, no significant difference in APTT ratios or plasma heparin concentrations were noted at any of the other sample times. AT III activity was not significantly different between the groups at any sample time. Within-group analysis showed significantly lower APTT ratio and heparin concentrations at 4 hours compared with the respective 2 hour values. These results would suggest that there is a potential impairment of anticoagulation with low-dose intravenous nitroglycerin and to a lesser extent with low-dose isosorbide dinitrate. Early and frequent monitoring may therefore be appropriate when intravenous nitrates and heparin are used in combination.

Background: Technetium-99m-methoxy-isobutyl-isonitrile (MIBI) has been shown to be a useful perfusion agent, and its improved imaging characteristics also allow evaluation of myocardial function. We evaluated the use of gated MIBI scintigraphy in patients undergoing percutaneous transluminal coronary angioplasty to show improvements in myocardial perfusion and function and to detect restenosis., Methods: Gated MIBI scintigraphy was performed in a preliminary study in 25 patients before angioplasty. Twenty-one patients who had undergone a successful procedure were re-examined 3 months later. Myocardial perfusion was evaluated and function measured using myocardial profiles along four axes., Results: Before angioplasty, 18 out of 21 patients had a reversible perfusion defect, and computer analysis of fractional shortening showed 19 out of 21 had abnormalities of left ventricular function during exercise. Only 11 out of 21 had a positive stress test. Mean global fractional shortening before angioplasty was 27.3% at rest and 26.6% during exercise (not significant). After angioplasty, left ventricular function was improved during exercise, with global fractional shortening increasing from 26.6% to 32.7% (P < 0.001). Repeat angiography was performed in 16 patients. Lesions in four patients had restenosed, in 11 they had not, and in one a different artery was occluded. Three of the four patients with restenosed lesions were identified using repeat perfusion imaging, and all four from abnormalities in left ventricular function. An abnormality in a new region was detected using both methods in the patient with the new occlusion. Normal perfusion and function were found in nine of the 11 patients without restenosed lesions. Two patients continued to have a positive stress test: one with a restenosed lesion and one with new disease., Conclusion: Dual assessment with gated MIBI scintigraphy provides useful data in patients undergoing angioplasty and may help in the selection of patients for repeat angiography.

A 31 year old man presented with a left hilar mass. Thoracic tomography showed this mass to be the pulmonary artery, and subsequently idiopathic dilatation of the pulmonary artery was diagnosed. He remained well until 11 years later when he died suddenly. Postmortem examination confirmed idiopathic dilatation of the pulmonary artery with death due to pulmonary artery dissection and cardiac tamponade. It seems likely that idiopathic dilatation of the pulmonary artery predisposed to fatal pulmonary artery dissection.

We have investigated the effects of low dose nitroglycerin on the activated partial thromboplastin time (APTT), plasma heparin concentration, antithrombin III activity (AT-III) and platelet factor 4 (PF4) levels in a group of 42 patients receiving intravenous heparin and low dose nitroglycerin (GTN) following percutaneous transluminal coronary angioplasty (PTCA). Venous samples were taken before PTCA and at 2, 4 and 24 h after the start of the infusions. Despite the heparin infusion being constant, the median APTT ratio (interquartile range) was significantly lower at the 4 h sample time compared to the 2 h sample time (4.4 [3.8-4.5] vs 2.6 [1.8-4.0], P < 0.05). At this time there was also a significantly lower median plasma heparin concentration compared to the 2 h sample (0.35 [0.2-0.7] vs 0.17 [0.1-0.3] P < 0.05). There were no significant differences in AT-III activity or PF4 levels at 4 h compared to the 2 h sampling time. In another group of patients (n = 20) who received intravenous heparin alone following PTCA also at 1000 U/h there were no significant differences in median APTT ratios (4.4 [4.3-4.5] vs 4.2 [2.9-4.5]), or in median plasma heparin concentrations (0.26 [0.14-0.96] vs 0.22 [0.18-0.87]) at 4 h compared to 2 h. Our observations confirm that nitroglycerin can interfere with the anticoagulant effect of heparin even at low doses. Although the exact mechanism involved remains unknown, this study suggests it is likely to be a result of a reduction in plasma heparin levels, perhaps through acceleration of normal heparin elimination.

We have compared the activated partial thromboplastin time with measurement of prothrombin fragment F1 + 2 concentrations (ELISA assay) during a 24-h period in a group of patients (n = 10) who had undergone elective coronary angioplasty and were anticoagulated post-procedure with heparin 1000 U/h. Four hours after the procedure all the patients were adequately anticoagulated according to activated partial thromboplastin time (median ratio 4.7:1) and the prothrombin fragment F1 + 2 concentration was significantly lower than pre-angioplasty values (0.5 vs 1.4 nmol/l, p = 0.04). At 24 h the median activated partial thromboplastin time ratio was still higher than the pre-procedure value (1.35 vs 0.9, p < 0.01), but the prothrombin fragment F1 + 2 concentration had risen to 2.1 nmol/l, with more variability in individual results within the patient group for the prothrombin fragment F1 + 2 concentration than for activated partial thromboplastin time (interquartile ranges (Q1, Q3) prothrombin fragment F1 + 2, 1.2-2.5; activated partial thromboplastin time, 1.2-1.5). The activated partial thromboplastin time is the standard method of monitoring the anticoagulant effect of heparin but may not fully reflect the functional coagulation status and accurately identify individual patients with less than adequate anticoagulation. Prothrombin fragment F1 + 2 concentrations may provide a more reliable indicator in individual patients of functional coagulation status in certain important situations where anticoagulation is critical such as following complicated coronary angioplasty.

Technetium-99m-methoxy-isobutyl-isonitrile (MIBI) is a myocardial perfusion agent which allows simultaneous assessment of left ventricular function. We evaluated left ventricular (LV) function with exercise using a new method of myocardial profiling in 43 patients with chest pain. Twenty-eight had significant coronary artery disease and 15 were normal on coronary angiography. Results were compared to equilibrium radionuclide ventriculography. MIBI fractional shortening (FS) correlated well with ejection fraction (EF) on exercise (r = 0.79, P = less than 0.001). There was also a good correlation between changes in global function from rest to exercise (r = 0.82, P = less than 0.001) with a sensitivity of diagnosing CAD of 71% and specificity of 80%. New regional wall abnormalities were detected in 25/28 with CAD with a sensitivity of 89% and specificity of 60%. There was also a close correlation between mean diameters measured with gated MIBI scans and volumes measured with RNV, end-diastolic diameter (EDD) versus end-diastolic volume (EDV) r = 0.78 (P = less than 0.001) at rest and r = 0.74 (P = less than 0.001) on exercise and end-systolic diameter (ESD) versus end-systolic volume (ESV) r = 0.72 (P = less than 0.001) at rest and r = 0.72 (P = less than 0.001) on exercise. This produced a sensitivity for detecting CAD of 79% and a specificity of 73%. These results show that gated MIBI scanning on exercise provides information comparable to RNV so enhancing the diagnostic usefulness of MIBI.

Technetium-99m methoxy-isobutylisonitrile, has been shown to be a useful perfusion agent for detecting coronary artery disease. Gated acquisition of perfusion images may remove motion artefact and improve detection. We compared the results of sensitivity and specificity for detecting coronary artery disease using perfusion images from the whole cardiac cycle (ungated) or from end-diastolic (gated) frames in 46 subjects, 31 with significant coronary disease and 15 with normal coronary arteries. There was no significant difference in detection of patients with coronary disease between the ungated and end-diastolic images: 25/31 with the ungated image and 28/31 with the end-diastolic. An improvement was made in detecting defects in the left anterior descending artery territory: 17/20 with the end-diastolic vs 11/20 with the ungated image (P less than 0.05) and in the right coronary artery region: 16/21 vs 10/21 (P less than 0.05), with an overall improvement in detecting regions supplied by stenosed coronary arteries: 45/55 end-diastolic vs 31/55 ungated (P less than 0.01). These results suggest use of the end-diastolic frame can significantly enhance the diagnostic capacity of methoxy-isobutylisonitrile perfusion imaging.

A 41-year-old Asian woman presented with mild congestive cardiac failure, initially controlled with a small dose of diuretic. Subsequently there was a marked deterioration in her condition with severe cardiac failure resistant to treatment. At this time biochemistry revealed a hyperphosphataemic variety of osteomalacia. Her cardiac failure improved promptly on correcting the hypocalcemia. Although hypocalcaemia is a recognised cause of cardiac failure it has not been described in privational osteomalacia.

The introduction of the 99Tcm isonitrile perfusion agents has provided improved myocardial image quality with conventional imaging equipment allowing improved edge definition on gating. We evaluated left ventricular wall motion in 46 patients using gated 99Tcm-2-methoxy-2-methyl-isopropyl-1-isonitrile (MIBI) scintigraphy. Using a method of myocardial profiles in four axes, global and regional fractional shortening (FS) were assessed. A good correlation was found between FS in the left anterior oblique (LAO) 40 degrees projection and ejection fraction (EF) on gated radionuclide ventriculography (r = 0.81, P less than 0.001). This was improved by using FS in two planes, LAO 40 degrees and anterior (r = 0.88, P less than 0.001). There was also a good correlation between FS in two planes and EF on cine-angiography (r = 0.72, P less than 0.001). There was good intra- and interobserver agreement with the studies. Assessment of myocardial function using gated MIBI imaging and myocardial profiles provides useful additional information to the perfusion scan, thus enhancing the diagnostic usefulness of the agent.

Coronary arteriovenous fistulas are rare and are usually diagnosed in children or young adults. Most are believed to be congenital. A right coronary arteriovenous fistula was first diagnosed in a patient of 74. Despite her age the fistula was successfully operated on and her symptoms were relieved.

A 46 year old man was found to have left ventricular outflow obstruction caused by a blood-filled cyst attached to the anterior papillary muscle of the mitral valve. It was successfully excised.

Dermal nitrate preparations are claimed to be useful in the treatment of angina, as their slow absorption by-passing the liver leads to a sustained action. Ten patients with angina were exercised on a treadmill after dermal application of 16.64 mg glyceryl trinitrate or 100 mg isosorbide dinitrate or placebo. Exercise duration was significantly increased at one and three hours for both nitrate preparations but not at six hours after application. The calculated workload achieved was significantly increased (p less than 0.01) at one and three hours for both preparations and at six hours (p less than 0.05) for isosorbide dinitrate. Headaches were common with glyceryl trinitrate cream. The dermal nitrate preparations studied had a duration of antianginal action similar to that of oral nitrate tablets. Aside from their value when the oral route cannot be used or absorption may be delayed, dermal nitrate preparations have no advantage over oral preparations for angina pectoris.

Basic and clinical studies were undertaken to determine pharmacokinetic mechanisms, blood flow-related characteristics and potential clinical utility of the 99mTc hexakis-t-butyl isonitrile (TBI) in the non-invasive diagnosis of ischemic heart diseases. Pharmacokinetic studies with TBI in animals demonstrated a high initial lung, heart and liver uptake. The lung clears at a relatively faster rate, the activity in the heart remained constant with a buildup of activity in the liver. These pharmacokinetic characteristics allowed for a myocardial imaging at 30-45 min post-injection at rest. The regional myocardial distribution of TBI was shown to be linearly related to microsphere-determined regional myocardial blood flow with a redistribution potential in transient ischemic myocardium (i.e., mimics 201Tl). The first pass extraction fraction (in vitro) for TBI was shown to be nearly 100% and independent on flow levels. In general, the slow tissue clearance rate or the lack of it might be due to the high degree of lipophilicity with the complete lack of any hepatic or extrahepatic metabolism to a less lipophilic metabolite. The complex demonstrated a high degree of cardiac membrane association. The net extraction in isolated heart slices was shown to be dependent on pH and temperature, independent of energy. The clinical studies demonstrated a similar pharmacokinetic pattern to the animal studies and documented the perfusion and ventricular function utility of TBI in the diagnosis of ischemic heart diseases.

Fifty-five patients of both sexes, aged 39-72, suffering from congestive heart failure of varying aetiology were admitted to a double blind study in which enalapril given in a dose of 5-10 mg twice daily or placebo was added to existing medication. A significant increase in exercise performance (P less than 0.004) was seen in the group treated with enalapril, an improvement which was still evident after 24 weeks of therapy. No significant difference was seen between the mean ejection fractions but subjective assessment suggested improvement in the enalapril-treated group.

Twenty-nine patients of 287 undergoing percutaneous transluminal coronary angioplasty (PTCA) were over 65 years old. These patients, mean age 67.2 years, were compared with 258 younger patients who had a mean age of 52.6 years. The primary success rate was 76% for the older and 79% for the younger patients. The rates for vessel occlusion, myocardial infarction, emergency surgery, and restenosis were similar in the two groups. When vessel occlusion occurred the results were more serious in the elderly and led to a fatality of 7%, compared with 0.4% for the younger patients. At 6 months' follow-up, 69% of those over 65 and 74% of those under 65 showed improvement in anginal symptoms. PTCA in older patients has similar immediate and short-term results to those in younger patients. However if complications occur, older patients have a higher fatality rate.

In 15 patients with acute myocardial infarction intravenous pentazocine in a dose of either 30 or 60 mg. was followed by a significant increase in mean pulmonary arterial pressure. In the group receiving the 60-mg. dose this change was associated with a significant increase in systemic arterial pressure, total peripheral resistance, and left ventricular minute work. Because of these circulatory effects intravenous pentazocine in a dose of 60 mg. would seem to be unsuitable for the relief of pain in myocardial infarction.

Chest electrodes are preferred to limb electrodes for cardiac monitoring, as limb movements are not restricted and produce less interference of the E.C.G. trace. Eight types of disposable chest electrodes were investigated to compare their performance, skin reactions, cost, ease of application, size, and skin-electrode impedance.Elema-Schonander electrodes were found to be the most efficient and the most expensive. In their application care was required to avoid severe skin reactions.Dracard electrodes were simple to attach, worked well without severe skin reactions, and were cheap. They are recommended for routine use. Smith and Nephew electrodes, a type of "multipoint electrodes" which do not require electrode jelly, frequently produced severe skin reactions, making them unsuitable for monitoring for periods exceeding 12 hours.

In a coronary care unit patients and electrocardiographic monitors are under almost continuous observation by trained personnel. This paper suggests that in a general medical ward without this facility routine cardiac monitoring with E.C.G. oscilloscopes is unlikely to lower the overall mortality from acute myocardial infarction. A mortality of 25% for acute myocardial infarction was the same for a hospital without a coronary care unit where monitoring was routinely performed and for two neighbouring hospitals which did not routinely use monitoring during the period of analysis.The need to train personnel in the recognition of E.C.G. monitor tracings and the difficulties associated with monitor alarm systems are emphasized.