Multivessel coronary thrombosis resulting from heparin induced thrombocytopenia.

Thrombosis associated with a drop in the platelet count may occur in 33-50% of the patients who develop heparin-induced thrombocytopenia (HIT) during treatment with unfractionated heparin. We report the case of a 63-year-old man who was treated with unfractionated heparin following a non-ST segment elevation myocardial infarction (NSTEMI). He developed an acute ST segment elevation infarction (STEMI) on day 3 with an associated severe thrombocytopenia. He was successfully treated with percutaneous intervention and aspiration of coronary thrombus from the right coronary artery and the left circulflex artery, followed by an infusion a direct thrombin inhibitor lepirudin/bivalirudin. He made an excellent recovery.

Early and mid-term outcomes after transcatheter aortic valve implantation (TAVI) in Ireland.

BACKGROUND: TAVI is a percutaneous approach to aortic valve replacement in high surgical risk patients deemed inoperable. AIM: To evaluate the early and mid-term outcomes for an Irish TAVI cohort over a six-year period at St James's Hospital and Blackrock Clinic, Dublin, Ireland. RESULTS: In total 147 patients, 56% male with an average age of 82 underwent TAVI between December 2008 and December 2014. Thirty day, one year and two year survival was 90.5%, 83% and 71% respectively. Major vascular complications and renal failure were the biggest predictors of mortality at 30 days (p = 0.02). We observed a pacing rate of 13.5%, the majority in patients who had Medtronic Corevalve implants (p < 0.05). With increasing procedural experience there was a reduction in length of stay from 10 days to 7.5 days. CONCLUSION: This review, the first of its kind in Ireland showed favorable rates of 30 day and one year and two year survival post TAVI with procedural success and complication rates similar to international registry data.

Bypass surgery versus stenting for the treatment of multivessel disease in patients with unstable angina compared with stable angina.

BACKGROUND: Earlier reports have shown that the outcome of balloon angioplasty or bypass surgery in unstable angina is less favorable than in stable angina. Recent improvements in percutaneous treatment (stent implantation) and bypass surgery (arterial grafts) warrant reevaluation of the relative merits of either technique in treatment of unstable angina. Methods and Results- Seven hundred fifty-five patients with stable angina were randomly assigned to coronary stenting (374) or bypass surgery (381), and 450 patients with unstable angina were randomly assigned to coronary stenting (226) or bypass surgery (224). All patients had multivessel disease considered to be equally treatable by either technique. Freedom from major adverse events, including death, myocardial infarction, and cerebrovascular events, at 1 year was not different in unstable patients (91.2% versus 88.9%) and stable patients (90.4% versus 92.6%) treated, respectively, with coronary stenting or bypass surgery. Freedom from repeat revascularization at 1 year was similar in unstable and stable angina treated with stenting (79.2% versus 78.9%) or bypass surgery (96.3% versus 96%) but was significantly higher in both unstable and stable patients treated with stenting (16.8% versus 16.9%) compared with bypass surgery (3.6% versus 3.5%). Neither the difference in costs between stented or bypassed stable or unstable angina ($2594 versus $3627) nor the cost-effectiveness was significantly different at 1 year. CONCLUSIONS: There was no difference in rates of death, myocardial infarction, and cerebrovascular event at 1 year in patients with unstable angina and multivessel disease treated with either stented angioplasty or bypass surgery compared with patients with stable angina. The rate of repeat revascularization of both unstable and stable angina was significantly higher in patients with stents.

Serial exercise testing in patients with effort angina: variable tolerance, fixed threshold.

To investigate the frequency and mechanism of variable threshold angina, seven treadmill exercise tests were performed in each of 28 patients with stable effort angina and exercise-induced ST segment depression. Each patient had tests at 8 AM on 4 days within a 2 week period and on 1 of these days had three additional tests at 9 AM, 11 AM and 4 PM. Time to 1 mm ST depression increased from 277 +/- 172 seconds on day 1 to 319 +/- 186 seconds on day 2, 352 +/- 213 seconds on day 3 and 356 +/- 207 seconds on day 4 (p less than 0.05). Rate-pressure product at 1 mm ST depression remained constant. Similarly, time to 1 mm ST depression increased from 333 +/- 197 seconds at 8 AM to 371 +/- 201 seconds at 9 AM and to 401 +/- 207 seconds at 11 AM and decreased to 371 +/- 189 seconds at 4 PM (p less than 0.01). Again, rate-pressure product at 1 mm ST depression remained constant. The standard deviation for time to 1 mm ST depression, calculated as a percent of the mean for each patient's seven tests and then averaged for the entire group, was 22 +/- 11%. The standard deviation for rate-pressure product at 1 mm ST depression, calculated in the same way, was significantly less at 8.4 +/- 2.8% (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

The radial artery: an alternative access site for diagnostic and interventional coronary procedures.

BACKGROUND: Percutaneous techniques are routinely used in the diagnosis and treatment of cardiovascular disease. The transfemoral route is the most frequently used arterial access site for performing these procedures AIM: To describe a technique to gain arterial access via the radial artery to perform diagnostic and invasive procedures. METHODS: Patient selection is key to establishing a successful transradial service. RESULTS: There is a significant vascular complication rate when using the transfemoral route. Transfemoral access can also be difficult in patients with peripheral vascular disease. Arterial access via the right radial artery represents a realistic alternative to the transfemoral route for performing diagnostic and therapeutic coronary procedures. CONCLUSIONS: The radial artery offers a safe and effective alternative access site for performing diagnostic and interventional coronary procedures. The need for alternatives to femoral artery access is critical in patients with severe peripheral vascular disease. The establishment and ongoing provision of radial artery intervention allows for a significant reduction in major vascular complication rates, earlier patient ambulation, increased patient comfort and the potential to establish day case coronary intervention.

Helicobacter pylori serology in patients with angiographically documented coronary artery disease.

We studied the relation between angiographically defined coronary artery disease and serologic evidence of Helicobacter pylori infection in 488 patients undergo ing elective coronary angiography. There was no association between Helicobacter pylori infection and coronary artery disease (odds ratio 1.3, 95% confidence interval 0.83 to 2.16).

Effect of intravenous and oral acebutolol in patients with bundle branch block.

We studied the effect of intravenous (1 mg/kg) and oral (400 mg) acebutolol on atrioventricular conduction in 22 patients with idiopathic bundle branch block and 1 to 1 atrioventricular conduction. Seven patients had previously symptomatic complete heart block (Group 1) and 15 were asymptomatic with bundle branch block only (Group 2). Following intravenous acebutolol heart rate decreased 82 +/- 16 to 63 +/- 16/min (P less than 0.01), A-H interval lengthened 98 +/- 22 to 121 +/- 30 msec (P less than 0.005) and H-V time was prolonged 60 +/- 13 to 70 +/- 17 msec (P less than 0.02) in those with previous heart block. The corresponding changes in the patients with no previous block were 74 +/- 14 to 61 +/- 8/min (P less than 0.01), 90 +/- 17 to 109 +/- 22 msec (P less than 0.05) and 48 +/- 15 to 56 +/- 14 msec (P less than 0.01). There was no difference between the basal or induced changes between these two groups. After intravenous acebutolol infusion 2 of 6 patients with previous spontaneous heart block and none of those without previous heart block developed atrioventricular block distal to His. The induced block was temporary (less than 10 min) and corresponded to the time of peak plasma acebutolol levels. Temporary atrioventricular block followed oral acebutolol administration in 4/7 patients with previous spontaneous heart block and 0/14 in those without block. In patients with bundle branch block intravenous acebutolol prolonged H-V conduction times in 19/20 patients and intravenous and oral acebutolol induced A-V block in 4/7 patients with previous spontaneous block.(ABSTRACT TRUNCATED AT 250 WORDS)

Relationship between intracoronary and peripheral expression of soluble cell adhesion molecules.

BACKGROUND: Elevated levels of soluble cell adhesion molecules (sCAMs) have been reported in various coronary artery disease processes. The principle stimulus for expression of sCAMs is believed to be an inflamed atherosclerotic plaque within the coronary vessel. The relationship between levels of sCAMs in the coronary circulation and the peripheral circulation has not been defined. The primary aim of this study was to define the relationship between levels of sCAMs sampled from the systemic circulation and from the coronary circulation. We also set out to document the acute expression of soluble CAMs following coronary angioplasty with or without stent implantation. METHODS: The coronary sinus was cannulated in patients undergoing LAD angioplasty. Samples were drawn from left coronary ostium (LCO) and coronary sinus (CS) and femoral vein simultaneously before, immediately after and 4 h after the PTCA procedure. Levels of sICAM-1, sVCAM-1, sE-selectin and sP-selectin were measured using ELISA technique. RESULTS: 10 patients (7 male/3 female, 61+/-11 y) entered the study. There was no significant difference in the levels of sICAM-1, sVCAM-1, sE-selectin and sPselectin whether sampled from left coronary ostium, coronary sinus or femoral vein at all time points. There was no significant change in the acute expression of sICAM-1, sVCAM-1 and sE-selectin following coronary angioplasty. Levels of sP-selectin fell significantly during the PTCA procedure (142+/-7 ng/ml to 64+/-6 ng/ml, P<0.001) but then rose again after 4 h and returned toward baseline levels at 24 h. CONCLUSION: Levels of soluble CAMs sampled in the systemic circulation directly reflect levels in the coronary circulation. Coronary angioplasty results in rapid fall in levels of sP-selectin which returns to normal within 24 h following the procedure.

The fractional distribution of the cardiac output in man using microspheres labelled with technetium 99m.

To investigate the distribution of organ blood flow in patients we have developed a method of quantitating the whole-body fractional distribution of 99Tcm-labelled microspheres. The microspheres were injected into the left ventricle in nine patients with normal cardiac indices (greater than 3 1/min/m2; Group A) and 11 patients with low cardiac indices (less than 2.51 l/min/m2; Group B). The fractional organ content of the total injected dose was estimated following correction for geometry and transmission using a gamma camera. Cerebral blood flow was 579 +/- 163 ml/min (mean +/- SD) in Group A and 593 +/- 158 ml/min in Group B (p not significant (NS)). Myocardial flow in Group A was 266 +/- 82 ml/min and in Group B was 237 +/- 57 ml/min (p, NS). Total renal blood flow was 749 +/- 161 ml/min in Group A and 614 +/- 181 ml/min in Group B (p less than 0.01). There was a negative correlation between cardiac index and the percentage of the cardiac output distributed to brain (r = -0.70, p less than 0.01), heart (r = -0.67, p less than 0.01) and kidneys (r = -0.47), p less than 0.05). Low output cardiac failure is, therefore, associated with relative preservation of cerebral and myocardial blood flow and, to a lesser extent, of renal flow. A similar technique using dual labelling would allow an accurate estimation in individual patients, of the change in organ blood flow associated with transient alterations in cardiac output states.

Problems related to the detection of myocardial ischemia caused by coronary vasospasm.

We compared the sensitivity of three commonly used provocative tests, exercise, ergonovine and the cold pressor test, in a series of 34 hospitalized patients with well-documented, active variant angina. All tests were performed off medication at the same time of day, usually on 3 consecutive days. Angina was provoked by ergonovine in all 34 patients, by exercise in 17 and by the cold pressor test in only 5 (p less than 0.005). ST elevation developed during the ergonovine test in 32 (94%), during exercise in 10 (29%) and during the cold pressor test in only 3 (9%). With ergonovine one patient had ST depression only and one had no ECG changes. During the cold pressor test two patients had pseudonormalization of abnormally negative T waves and 29 had no ECG changes. Exercise induced T wave pseudonormalization in 4 patients, ST depression in 9 others and no ECG changes in 11. Thus, in patients with active variant angina, the sensitivity of the cold pressor test and exercise are too low to be useful clinically. Other studies suggest that the sensitivity of hyperventilation or provoked alkalosis is higher, but not as high as ergonovine administration. In patients who have become asymptomatic, either with treatment or spontaneously, the sensitivity of all tests decreases markedly. If such patients no longer have coronary spasm, the test is not a 'false negative' but a 'true negative'. Deaths have been reported following ergonovine administration and for this reason the test is not universally accepted.(ABSTRACT TRUNCATED AT 250 WORDS)

Intra-coronary stents--extending the role of angioplasty in angina--initial experience.

Percutaneous transluminal coronary angioplasty (PTCA) is a widely successful revascularisation procedure. The restenosis rate has not significantly improved, despite the addition of many therapeutic agents. We describe the role of intra-coronary stents in the management of recurrent occlusion, restenosis and intracoronary dissection. We describe and discuss the problems associated with placement of the stent. The intracoronary stent has a successful adjuvant role to play with angioplasty in reducing both the elective and emergency requirements for coronary artery bypass grafting.

Immediate and follow-up results of coronary angioplasty--lessons for the future.

In a series of 129 patients having coronary angioplasties in St. James's Hospital in 1989, the average age was 54.8 (30-77 years). There were 102 (79%) men and 27 (21%) females. Clinical indications were unstable angina 62, stable angina 26, post myocardial infarction 39 and asymptomatic ischaemia 2. The distribution of coronary disease was single vessel 62%, double vessel 28%, triple vessel 7% and previous coronary bypass surgery 3%. Only 10 patients had more than one vessel dilated. Primary success was achieved in 119 (92%), there were no deaths, 3 patients had abrupt closure of the vessel during angioplasty and sustained a nonfatal myocardial infarction, 1 patient required urgent bypass surgery and 2 patients had peripheral vascular complications requiring surgery. There were 6 failed angioplasties, 4 of which had chronic total occlusion. At a mean follow-up of 5.3 months, 85 patients had no symptoms, 34 had angina, 2 developed myocardial infarction and 1 died suddenly at 5 months. Repeat angiography was performed in 96 (79%) patients. At follow-up, no symptoms were present in 69% of those with single vessel disease and 70% of multivessel disease. Of those who had more than one vessel dilated in multivessel disease, 80% were asymptomatic (P = NS). There were 11 patients with initial total occlusion at presentation, 4 had failed angioplasties, 5 recurrent angina of which 4 reoccluded and 1 restenosed and only 2 were asymptomatic and without restenosis. Angioplasty was performed with primary success (92%) and follow up results (70% asymptomatic). Those with single or multivessel disease had similar clinical outcome, favouring the use of target vessel angioplasty. Long term results following angioplasty of chronic total occlusions were poor and suggests the need for additional treatment.

Transluminal angioplasty of a stenosis of an internal mammary artery graft.

Stricture of an internal mammary artery graft was successfully dilated by percutaneous angioplasty in a young man who had recurrent angina soon after bypass surgery.

Aorto-atrial fistula in rheumatoid arthritis.

A patient with severe deforming rheumatoid arthritis presented with a short history of chest pain. The clinical signs were of an unusual diastolic murmur and profound shock unresponsive to therapy. Post-mortem examination disclosed the unexpected finding of a large aorto-atrial fistula.

An echocardiographic study of localized subaortic hypertrophy.

A prospective echocardiographic investigation was undertaken to determine the prevalence and significance of localized subaortic hypertrophy in 1000 consecutive patients presenting for a routine echocardiographic examination. Localized septal hypertrophy was diagnosed when the subaortic septum was hypertrophied (greater than 1.4 cm) and was 50% thicker than the mid-point of the septum. Patients with hypertrophic cardiomyopathy and fixed subvalvular aortic stenosis were excluded. Eight cases of localized subaortic hypertrophy were identified. In 7 the appearances of the left side of the interventricular septum were similar with an apparently sigmoid shape (reversed S on its side) and in 1 with associated mitral stenosis the septum was a tapered wedge. All patients with localized subaortic hypertrophy had left ventricular hypertrophy (left ventricular mass or posterior wall thickness greater than 2 SD from normal) with a normal size cavity due to aortic valve disease (2 patients were also hypertensive). Of the 180 patients with aortic valve disease, localized subaortic hypertrophy was found in 10% of those with left ventricular hypertrophy and 33% of those with asymmetrical septal hypertrophy (septum to posterior wall ratio of greater than 1.5:1). There was no evidence of subaortic stenosis by pulsed and continuous wave doppler echocardiography (8 cases) and cardiac catheterization (6 cases). The aetiology of this discrete localized muscular bulge is unclear but is presumably due to change in shape of the septum with left ventricular hypertrophy. However, this finding has important implications as a cause of asymmetrical septal hypertrophy and because of the possible false diagnosis of subvalvular stenosis and its effect on ultrasound measurements.

Failure of transdermal nitroglycerin to improve chronic stable angina: a randomized, placebo-controlled, double-blind, double crossover trial.

We assessed the effect of transdermal nitroglycerin (NTG-TTS), releasing 5 mg/24 hr, in 11 patients with chronic stable angina during a randomized, placebo-controlled, double-blind, double crossover trial of four 1-week periods. All patients had a positive exercise test and coronary artery disease prior to entry into the study. Efficacy was assessed weekly by anginal diaries, ambulatory ST segment recordings, and computerized exercise testing 2 to 4 hours after renewal of NTG-TTS. One patient withdrew in the first week (placebo) and was excluded from all analysis. The weekly frequency of anginal attacks was 9 +/- 11 (mean +/- SD) and 9 +/- 10 during the 2 placebo weeks and 11 +/- 14 and 9 +/- 11 during NTG-TTS; the time to 1 mm ST segment depression (seconds) was 268 +/- 178 and 303 +/- 217 with placebo and 228 +/- 221 and 285 +/- 178 with NTG-TTS; exercise duration (seconds) was 375 +/- 230 and 467 +/- 254 during placebo and was 394 +/- 233 and 412 +/- 236 during NTG-TTS. The weekly number of episodes of ST depression was 11 +/- 9 and 8 +/- 5 during placebo and 8 +/- 5 and 9 +/- 7 during NTG-TTS. Our study failed to show any consistent differences in patients treated with placebo or NTG-TTS.

Comparative antianginal effects of nisoldipine and nifedipine in patients with chronic stable angina.

The acute antianginal effects of 5 mg and 20 mg nisoldipine were compared with 20 mg nifedipine and placebo. Maximal treadmill exercise testing was performed before and 3 hours after drug administration in 10 patients with chronic stable angina. Resting heart rate and systolic blood pressure were unchanged following low-dose nisoldipine, but 20 mg nisoldipine and 20 mg nifedipine increased heart rate and decreased systolic arterial pressure (p less than 0.05). Time (in seconds) to the onset of 0.1 mV ST segment depression was significantly prolonged after 5 mg nisoldipine (+60 +/- 53; p less than 0.05) and 20 mg nisoldipine (+100 +/- 78; p less than 0.01) but not after 20 mg nifedipine (+48 +/- 131; p = NS). Total exercise duration increased significantly following 5 mg and 20 mg nisoldipine (p less than 0.01 and p less than 0.001, respectively) but only slightly following nifedipine (p = NS). The maximal rate-pressure product was increased to a similar degree following doses of both nisoldipine and nifedipine (p less than 0.05). Nisoldipine is an effective antianginal agent which performs well in comparison to nifedipine.

The variable effects of angiotensin converting enzyme inhibition on myocardial ischaemia in chronic stable angina.

The effect of angiotensin converting enzyme inhibition on myocardial ischaemia was studied in 12 normotensive patients with chronic stable angina and exercise induced ST segment depression. The study was randomised, double blind, placebo controlled, and crossover with treatment periods of two weeks. Enalapril was used to inhibit angiotensin converting enzyme. Assessment was by angina diaries and maximum symptom limited treadmill exercise tests. The results for the whole group showed a significant reduction in systolic blood pressure at rest and at peak exercise. Mean total exercise duration was 466 s (95% confidence interval 406 to 525) when the patients were taking placebo and 509 s (436 to 583) when they were taking enalapril. Four patients prolonged their total exercise time (mean 450 to mean 591 s) by more than 20%. Two patients, however, developed ischaemia earlier on exercise and reduced their total exercise duration (mean 490 to mean 390 s). Although angiotensin converting enzyme inhibition tended to reduce myocardial ischaemia in the group as a whole, some patients improved while others deteriorated. Thus the effects of enalapril are variable and this may have important implications when enalapril is used to treat heart failure in patients with underlying severe ischaemic heart disease.

Angiographic findings after myocardial infarction in patients with previous bypass surgery: explanations for smaller infarcts in this group compared with control patients.

The incidence of previous coronary artery bypass surgery (CABS) in patients with acute myocardial infarction admitted to our hospital has risen from 2.3% to 11.2% in 6 years. We compared infarct size and the angiographically determined cause of infarction in 52 control patients and in 52 consecutive patients with acute myocardial infarction at least 2 months after they had undergone CABS. Baseline characteristics were similar in both groups except for a higher incidence of preexisting Q waves in the post-CABS group (22 vs 10; p less than .05). Indexes of myocardial infarct size were smaller in the post-CABS group compared with those in control patients: peak creatine kinease (CK) level (IU/liter) 1113 +/- 1094 (mean +/- SD) vs 1824 +/- 1932 (p less than .01), peak CK-MB level (IU/liter) 173 +/- 230 vs 272 +/- 332 (p less than .02), peak summed ST segment elevation (mm) 3.5 +/- 4.8 vs 8.2 +/- 9.9 (p less than .005), and QRS score on days 7 to 10, 1.9 +/- 3.0 vs 4.3 +/- 3.4 (p less than .001). Postinfarction left ventricular ejection fraction was higher in the post-CABS group (53 +/- 13%) compared with that in control patients (47 +/- 12%; p less than .05). The incidence of total occlusion of the artery to the infarct zone was similar in the post-CABS and control patients (33 vs 27), as was the incidence of one-, two-, and three-vessel disease (artery plus graft). Collateral blood flow to the infarct zone was found in 27 post-CABS patients and in 23 control patients.(ABSTRACT TRUNCATED AT 250 WORDS)