Coronary artery perforation during percutaneous intervention: incidence and outcome.

OBJECTIVE: To examine the clinical outcome of percutaneous coronary intervention where the procedure was complicated by vessel perforation. SETTING: Tertiary referral centre. METHODS: The procedural records of 6245 patients undergoing coronary intervention were reviewed. In 52 patients (0.8%) the procedure was complicated by vessel perforation, ranging from wire exit to free flow of contrast into the pericardial space. The majority of lesions treated were complex (37% type B, 59% type C) and 9 of 52 (17%) were chronic occlusions. Ten patients (19%) received abciximab. Four underwent rotational atherectomy (8%). RESULTS: In 28 of 52 patients (54%) the perforation was benign and managed conservatively without the development of haemodynamically significant sequelae. In 24 of 52 (46%) a significant pericardial effusion ensued requiring drainage. Of these 24 procedures 6 had involved the treatment of a chronic occlusion (25%). Eight of the 24 patients were referred for emergency bypass surgery (33%), 3 of whom died. Of the remaining 16 not referred for surgery, 3 died. Of the 10 procedures complicated by vessel perforation where abciximab had been administered, 9 (90%) led to pericardial tamponade. Latterly 2 vessel perforations were successfully treated by the deployment of a covered stent. CONCLUSIONS: Coronary artery perforation with sequelae during intervention is rare--26 of 6245 (0.4%). This complication was seen in the treatment of chronic occlusions, which are therefore not risk-free procedures. The development of pericardial tamponade carries a high mortality. While prompt surgical intervention may be life saving, expertise in the use of covered stents may provide a valuable rescue option for this serious complication. Caution should be exercised where coronary perforation occurs and abciximab has been used.

Development and validation of a Bayesian index for predicting major adverse cardiac events with percutaneous transluminal coronary angioplasty.

OBJECTIVE: To create a risk model for predicting major adverse complicating events of percutaneous transluminal coronary angioplasty (PTCA), and to test the accuracy of the model on a prospective cohort of patients SETTING: Tertiary cardiac centre METHODS: Available software can predict probabilities of events using Bayes's theorem. To establish the accuracy of these predictive tools, a Bayes table was created to evaluate major adverse complicating events (MACE)-death, emergency coronary artery bypass grafting (CABG), or Q wave infarct occurring during the in-patient episode-on the first 1500 patients in the department PTCA database (development group); the predictive value of this model was then tested with the subsequent 1000 patients (evaluation group). The following probabilities were assessed to determine their association with MACE: age, sex, left ventricular function, American Heart Association lesion morphology classification, cardiogenic shock, previous CABG, diabetes, hypertension, multivessel PTCA. MAIN OUTCOME MEASURES: To establish the discriminatory ability of the predictive index, calibration plots and receiver operating characteristic (ROC) curves were obtained to compare the development and evaluation groups. RESULTS: The ROC curve plotted to determine the discriminatory value of the Bayesian table created from the development group (n = 1500) in predicting MACE in the evaluation group (n = 1000) showed a moderately predictive area under the curve of 0.76 (SEM 0.07). This predictive accuracy was confirmed with separately constructed calibration plots. CONCLUSIONS: Accurate predictions of MACE can be identified in populations undergoing percutaneous intervention. The database used allows operators to obtain consent from patients appropriately from their own experience rather than from other published data. If a national PTCA database existed along similar lines, individual operators and interventional centres could compare themselves with nationally available data.

Angiographic and clinical restenosis following the use of long coronary Wallstents.

This study assessed clinical and angiographic restenosis following the deployment of the long coronary Wallstent. Between May 1995 and June 1997, 182 Wallstents were deployed in 162 vessels in this unit. Forty-eight percent had an unstable coronary syndrome and 94% had AHA grade B or C lesions. The mean lesion length was 37 +/- 20 mm and the mean stent length was 48 +/- 20 mm. The procedural success rate was 99% and the primary success rate was 93%. Six in-patients suffered subacute stent thrombosis, the majority being in the era of anticoagulation rather than antiplatelet regimes. Seventy-three percent remained free of major adverse clinical events in the follow-up period, but 41% had angiographic restenosis. The Wallstent can be deployed in complex lesions with a high primary success rate and an acceptably low restenosis rate. The optimal management of in-stent restenosis remains to be defined.

Evaluation of myocardial, hepatic, and renal perfusion in a variety of clinical conditions using an intravenous ultrasound contrast agent (Optison) and second harmonic imaging.

OBJECTIVE: To assess the potential of intravenous Optison, a second generation ultrasound contrast agent, and various ultrasound imaging modes to determine myocardial, kidney, and liver perfusion in normal subjects and patients with left ventricular dysfunction or chronic pulmonary disease together with renal or hepatic dysfunction. METHODS: Five normal subjects and 20 patients underwent grey scale echocardiographic imaging of myocardium, kidney, and liver during 505 intravenous injections of Optison. Images were assessed qualitatively by two independent observers and quantitatively using video densitometry to determine the peak contrast enhancement effect. RESULTS: Qualitative analysis showed that intermittent harmonic imaging was superior to either conventional fundamental or continuous harmonic imaging for all organs. Quantitative analysis showed that the peak change in echocardiographic intensity v baseline during continuous harmonic imaging was 11 units for myocardium (p < 0.03), 7 units for kidney (NS), and 14 units for liver (p < 0.05). During intermittent harmonic imaging the peak change was significantly greater, being 33 units for myocardium (p < 0.0001), 24 units for kidney (p < 0.0002), and 16 units for liver (p < 0.001). CONCLUSIONS: Organ tissue perfusion can be demonstrated following intravenous injection of Optison, particularly when used in combination with intermittent harmonic imaging techniques. This contrast agent is effective in a variety of clinical conditions.

Randomised trial of elective stenting after successful percutaneous transluminal coronary angioplasty of occluded coronary arteries.

BACKGROUND: The value of angioplasty in occluded coronary arteries is limited by a restenosis/reocclusion rate of 50-70%. In patients with subtotal occlusion, stent implantation has been shown to reduce clinical and angiographic restenosis. Retrospective observational studies have suggested that stenting could reduce restenosis in total occlusions. The value of sustained coronary patency on global and regional left ventricular function in this clinical setting has not been defined clearly. OBJECTIVES: To assess the medium term effect of elective intracoronary stent deployment after successful percutaneous transluminal coronary angioplasty (PTCA) of an occluded coronary artery. METHODS: Sixty patients with a total coronary occlusion successfully treated by PTCA were randomised to receive an intracoronary stent or no stent. Patients underwent clinical and angiographic follow up at six months. RESULTS: Thirty patients received a stent (group A) and 30 were treated by angioplasty alone (group B), all with initial success. One patient in group B required repeat angioplasty with stenting at 24 hours and one patient died after 10 days. Angiographic follow up was available for 57 patients. This showed a significantly reduced reocclusion rate in group A compared with group B (7% v 29%, p < 0.01) and a tendency to a reduced restenosis rate (22% v 40%, p = 0.105) in patients with no reocclusion. Left ventricular function, both global and regional, improved in group A. Only the regional left ventricular function in the area supplied by the target coronary artery improved in group B. Recurrence of symptoms and clinical events such as repeat angioplasty, coronary artery bypass grafting, death or myocardial infarction tended to be reduced in group A (4 (13%) v 9 (30%)). CONCLUSIONS: Intracoronary stent insertion is effective in reducing the rate of reocclusion and shows a trend towards reduced restenosis after opening of a total coronary occlusion by balloon angioplasty. Sustained patency of the target coronary artery is associated with improvement in global and regional left ventricular function.

Spontaneous haemothorax as a complication of anti-coagulation following coronary angioplasty.

Haemorrhagic complications are well recognized when heparin is used during percutaneous transluminal coronary angioplasty (PTCA). We present a 74-year-old female who developed a large acute spontaneous haemothorax 20 h after coronary angioplasty. Spontaneous haemothorax has rarely been described and is predominantly associated with pulmonary embolism. In the absence of a pulmonary embolus, a spontaneous haemothorax during anti-coagulation has only been described twice in the world literature since 1862 (1). This is the first description of this complication following the use of heparin during PTCA.

Comparison of clinical outcome after elective and "bail out" coronary stent insertion.

BACKGROUND: Coronary stents may be used electively during percutaneous transluminal coronary angioplasty (PTCA) or as a "bail-out" device to treat abrupt or threatened vessel closure following PTCA. OBJECTIVE: To compare the clinical outcome of elective and "bail-out" coronary stent insertion. DESIGN: A retrospective analysis of all patients receiving coronary stents. SETTING: Tertiary referral center performing over 400 PTCA procedures a year. PATIENTS: Fifty-six patients (42 male), mean age 57 (range = 32 to 78) years received 67 Palmaz-Schatz coronary stents. Forty-nine stents were deployed as "bail-out" in 41 patients (abrupt vessel closure in 15 and threatened vessel closure in 26) and 18 stents were deployed electively in 15 patients. MAIN OUTCOME MEASURES: Myocardial infarction, repeat angiography, coronary artery bypass graft surgery and death. RESULTS: Stents were successfully deployed in 56/62 (90.3%) patients. In-hospital events were significantly more common in the "bail-out" group compared to the elective group. The in-hospital events, comparing the "bail-out" group versus the elective group, were as follows: Death 2/41 (4.9%) vs 0/15 (0%), coronary artery bypass graft surgery (CABG) 8/41 (19.5%) vs 0/15 (0%), stent thrombosis 3/41 (7.3%) vs 0/15 (0%), and myocardial infarction 6/41 (14.6%) vs 1/15 (6.7%) respectively. After discharge no patient died or had CABG. One patient in the "bail-out" group had a myocardial infarct (late stent thrombosis). Two patients from each group had repeat angiography because of recurrent angina in the 6 month follow up period. CONCLUSION: "Bail-out" stenting has an increased incidence of in-hospital complications compared to elective procedures. If these short-term problems can be overcome however, the clinical events in the first 6 months after leaving hospital are low and similar to patients under-going elective procedures.

Echocardiographic assessment of systolic and diastolic left ventricular function using an automatic boundary detection system. Correlation with established invasive and non invasive parameters.

Systolic and diastolic left ventricular function was assessed using an echocardiographic automatic boundary detection system (ABD) in 50 unselected patients undergoing left cardiac catheterisation. Automatic boundary detection system derived parameters (fractional area change [FAC], peak positive rate of area change [+dA/dt] and peak negative rate of area change [-dA/dt]) were compared with invasively (left ventricular angiography and pressures) and non invasively (Doppler mitral filling velocities and isovolumic relaxation time) acquired conventional indices of ventricular function. Adequate detection of endocardial boundaries and subsequent measurements using the ABD system were achieved in 40/50 (80%) patients in the short axis parasternal view, in 41/50 (82%) in the apical four chamber view and in 34/50 (68%) in both views. For the whole group of patients the FAC (maximal left ventricular diastolic area--minimal left ventricular systolic area/maximal left ventricular diastolic area) estimated in the short axis view correlated with the angiographic ejection fraction (EF) measured in the right oblique projection (r = 0.51, p < 0.001). There was only a weak correlation of the FAC estimated in the apical four chamber view with the EF (r = 0.36, p < 0.01). The mean FAC (mean value of the FAC in the short axis and apical four chamber views) correlated reasonably with the EF (r = 0.62, p < 0.0001). There was no correlation between ABD derived parameters and left ventricular end diastolic pressure (LVEDP) in these patients. In a subgroup of patients with normal coronary arteries and left ventricular function (n = 17), although there was no correlation between EF and FAC, there was a strong positive correlation between FAC (apical four chamber and mean) and LVEDP (r = 0.77, p < 0.01 and r = 0.87, p < 0.01 respectively). No correlation was found in these patients between EF and LVEDP. In a further subgroup of patients with angiographically abnormal left ventricular function (EF < 45%), there was a positive correlation between FAC (short axis, apical four chamber and mean) and EF (r = 0.52, p < 0.05, r = 0.83, p < 0.0001 and r = 0.80, p < 0.001 respectively) and a negative correlation between FAC (short axis and mean) and LVEDP (r = -0.52, p < 0.05 and r = -0.60, p < 0.01 respectively). There was also a negative correlation between LVEDP and EF in the same subgroup of patients (r = -0.65, p < 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)

Recanalization of coronary occlusions using the Magnarail system: technique and procedural outcome.

Angioplasty for occluded coronary arteries is less successful than for sub-total stenoses. The Magnarail system (Schneider) has been designed to improve success rates. We used the system in 112 patients with coronary occlusions (TIMI flow < or = 1) which the operator felt suitable for angioplasty. It was successful (defined as < 50% stenosis) in 75.9% overall, 65.9% in occlusions > 3 months and 83.3% < 3 months. Intimal dissection occurred in 26 instances, more commonly after right coronary angioplasties. One patient died and one procedure was complicated by coronary perforation treated surgically. The procedure was less successful in the right coronary artery (p = 0.02). Coronary calcification (p = 0.03), the absence of a tapered occlusion (p = 0.04) and the absence of collaterals from another vascular territory (p = 0.04) were all associated with angiographic failure. The mean fluoroscopy time for the procedures was 22.8 +/- 16.9 minutes. The Magnarail system seems highly effective in recanalization of coronary occlusions.

The value of transthoracic echocardiography during percutaneous balloon mitral valvuloplasty.

Percutaneous balloon mitral valvuloplasty is a standard alternative to surgery in a selected group of patients with symptomatic dominant rheumatic mitral stenosis. With careful transthoracic and transesophageal echocardiographic selection of patients, there is a low complication and high success rate. Echocardiography has also been established as extremely useful in the long-term follow-up of patients. We present four cases that highlight our view that transthoracic echocardiography should be performed during the procedure, after each balloon inflation, and before and after the intervention. In our experience transthoracic echocardiography during balloon mitral valvuloplasty is invaluable in assessing commissural separation, increasing mitral valve area, new mitral regurgitation, and occasional unexpected anatomic sequelae of balloon inflation.

Identification of reversible ischaemia after acute myocardial infarction using thallium tomography with early and delayed imaging after resting injection.

We studied 30 patients 6 weeks after first myocardial infarction in order to compare early and delayed imaging after resting injection of thallium for the detection of viable myocardium. Twenty-six of the 30 patients studied had received thrombolysis. Conventional stress and redistribution thallium tomography was followed by a resting injection of thallium with imaging immediately after in all patients and 3 h later in a subgroup of 15 patients. Thallium uptake was graded semi-quantitatively in each of nine myocardial segments. Eighty-eight of the 270 segments had a fixed defect on redistribution imaging, 40 (45%) of which had improved uptake in the immediate reinjection images. Only 9 of 135 (6%) segments with fixed defects on immediate reinjection imaging showed additional uptake with delayed reinjection imaging. These data suggest that imaging early after thallium reinjection is of value in the detection of reversible ischaemia after infarction, but that delayed reinjection imaging offers little additional benefit.

Improved assessment of inferior left ventricular wall motion using biplane equilibrium radionuclide ventriculography.

Equilibrium radionuclide ventriculography is often restricted to the left anterior oblique projection. The differential sensitivity of left anterior oblique amplitude and phase images for anterior and inferior infarction was evaluated using quantitative analysis, and the role of left posterior oblique images assessed. Twenty anterior infarcts, 20 inferior infarcts and 20 normal controls were studied. Left anterior oblique amplitude and phase abnormalities were seen in 100% (20) and 85% (17) of anterior infarcts but only 55% (11) and 50% (10) of inferior infarcts. Left posterior oblique amplitude and phase abnormalities were seen in 95% (19) of anterior infarcts and 75% (15) and 85% (17) of inferior infarcts. Left anterior oblique standard deviation of phase differed from normal only for anterior infarction (P < 0.01); both anterior and inferior (P < 0.05) infarction differed from normal in the left posterior oblique projection. Left anterior oblique images are therefore insensitive for inferior infarction. An accurate description of regional ventricular wall motion requires biplane radionuclide ventriculography.

A randomised comparison of the Omniflex and Magnarail systems in recanalisation of coronary occlusions.

OBJECTIVE: The reported success rates for angioplasty of occluded coronary arteries fall some way short of the success rates for angioplasty of sub-occlusive stenoses. Two angioplasty systems used in this setting were compared. DESIGN: A prospective randomised open study comparing the Magnarail system (Schneider) and the Omniflex system (Medtronic). SETTING: A regional cardiothoracic centre performing over 300 angioplasty procedures a year. PATIENTS AND METHODS: 50 consecutive patients with occluded (thrombolysis in myocardial infarction study (TIMI) grade 0 or 1) arteries thought to be suitable for recanalisation were assigned to undergo angioplasty with either the Magnarail or Omniflex as the primary system. Twenty minutes of fluoroscopic screening was allowed with the primary randomised system before it was considered a failure. The other non-randomised system could then be used at the operators' discretion, and a further 20 minutes' screening was permitted. MAIN OUTCOME MEASURES: A patent coronary artery with a residual stenosis of < 50% with prompt distal opacification (TIMI grade 3 flow) and a reduction in collateral supply to the index artery. RESULTS: The overall success rate in recanalising occluded vessels was 72%-64% for the Magnarail system used as the primary system and 51.7% for the Omniflex (NS). The Magnarail was more successful in angioplasties of the right coronary artery (11/14 v 3/10, p = 0.02) and in mid and distal sites of occlusion (11/17 v 4/14, p < 0.05). There was a trend in favour of the Omniflex in the left anterior descending coronary artery. CONCLUSION: Both systems would seem to be suitable for angioplasty of occluded coronary arteries. The improved steerability of the Magnarail may be advantageous in distal occlusions and lesions in tortuous arteries. The relatively stiffer Omniflex may be superior for proximal occlusions. The study group was too small to confirm this unequivocally.

Digital radiofrequency echocardiography in the detection of myocardial contrast following intravenous administration of Albunex.

Conventional contrast echo techniques have proved inadequate for the detection of myocardial perfusion using intravenously injected echo contrast agents because of the limitations and relative insensitivity of standard echocardiographic equipment. In order to avoid these problems, we have obtained pure digital radiofrequency ultrasound data from the left ventricle and myocardium during i.v. contrast myocardial perfusion echo studies. In 30 patients, following coronary arteriography, i.v. injections of the echo contrast agent Albunex (sonicated human serum albumin) in two doses of 0.08 and 0.22 ml.kg-1 were administered during digital radiofrequency echocardiography sampling of data from the myocardium and left ventricular cavity. Analysis of mean integrated backscatter (MIB, a measure of the total ultrasound energy) was performed before, during and after Albunex injection. The data were also analysed for a shift in frequency spectrum which could be caused by resonance of the Albunex contrast microspheres in the heart, a phenomenon which has been previously demonstrated in vitro. Digital radiofrequency ultrasound data were successfully obtained and analysed in 23 patients. In 31 segments where reasonable resting perfusion was expected, there was a significant increase in MIB from 0.644 to 1.245, P < 0.001 and time intensity curves could be constructed showing wash-in and wash-out of contrast from the myocardium. In 10 segments supplied by significantly diseased vessels, MIB intensity increased from 1.044 to 1.874, P = 0.054. In myocardial segments supplied by non-diseased vessels, microsphere resonance also caused a drop in mean frequency of 140 KHz, P < 0.001, and permitted similar temporal analysis of myocardial perfusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Endocrine and cardiac paracrine actions of insulin-like growth factor-I (IGF-I) during thyroid dysfunction in the rat: is IGF-I implicated in the mechanism of heart weight/body weight change during abnormal thyroid function?

Thyroid hormones are essential for the normal growth and development of many tissues. In the rat, hypothyroidism is associated with growth impairment, and hyperthyroidism with the development of a hypercatabolic state and skeletal muscle wasting but, paradoxically, cardiac hypertrophy. The mechanism by which thyroid hormone produces cardiac hypertrophy and myosin isoenzyme changes remains unclear. The role of IGF-I, an anabolic hormone with both paracrine and endocrine actions, in producing cardiac hypertrophy was investigated during this study in hyperthyroid, hypothyroid and control rats. A treated hypothyroid group was also included in order to assess the effect of acute normalization of thyroid function. Body weight was significantly lower in the hyperthyroid (mean +/- S.E.M.; 535.5 +/- 24.9 g, P < 0.05), hypothyroid (245.3 +/- 9.8 g, P < 0.001) and treated hypothyroid (265.3 +/- 9.8 g, P < 0.001) animals when compared with controls (618.5 +/- 28.6 g). Heart weight/body weight ratios were, however, significantly increased in the hyperthyroid (2.74 +/- 0.11 x 10(-3), P < 0.01) and treated hypothyroid (2.87 +/- 0.07 x 10(-3), P < 0.001) animals when compared with controls (2.26 +/- 0.03 x 10(-3). Serum IGF-I concentrations were similar in the control and hyperthyroid rats (0.91 +/- 0.07 vs 0.78 +/- 0.04 U/ml, P = 0.26), but bioactivity was reduced by 70% in hyperthyroid serum, suggesting a circulating inhibitor of IGF. Serum IGF-I levels (0.12 +/- 0.03 U/ml, P < 0.001) and bioactivity (0.12 +/- 0.04 U/ml, P < 0.001) were significantly lower in the hypothyroid group. Liver IGF-I mRNA levels were not statistically different in the control and hyperthyroid animals, but were significantly reduced in the hypothyroid animals (P < 0.05 vs control). Heart IGF-I mRNA levels were similar in the control and hypothyroid rats, but were significantly increased in the hyperthyroid and treated hypothyroid animals (increased by 32% in hyperthyroidism, P < 0.05; increased by 57% in treated hypothyroidism, P < 0.01). Cardiac IGF-I was significantly elevated in hyperthyroidism (0.16 +/- 0.01 U/mg heart tissue, P < 0.01), was low in hypothyroidism (0.08 +/- 0.01 U/mg, P < 0.01) and was normalized in the treated hypothyroid group (0.11 +/- 0.01 U/mg vs control, 0.13 +/- 0.01 U/mg). Low body mass during both hypothyroidism and hyperthyroidism is therefore associated with reduced systemic IGF bioactivity. In hypothyroidism there is a primary defect in the endocrine function of IGF-I, while in hyperthyroidism serum IGF bioactivity is reduced in the presence of normal endocrine production of this anabolic hormone.(ABSTRACT TRUNCATED AT 400 WORDS)

Influence of platelet size before coronary angioplasty on subsequent restenosis.

Platelet size has been shown to reflect platelet activity. We prospectively measured the mean platelet volume (MPV) in 47 patients undergoing single vessel angioplasty for symptomatic angina. The patients underwent repeat angiography 4-8 months later irrespective of symptomatic status. Restenosis was assessed quantitatively by hand held calliper measurements of the lesion and qualitatively by a return of angina, ST segment changes on an exercise test and visual analysis of the lesion severity by two experienced angiographers. Twenty-four patients developed recurrent angina during the follow-up period, the MPV in the group with chest pain was 8.54 +/- 0.60 fl compared to 8.1 +/- 0.69 fl in the asymptomatic group (P = 0.04). Twenty two patients had significant ST segment changes at exercise. In this group the MPV was 8.6 +/- 0.56 fl compared to 8.0 +/- 0.70 fl for the group with a negative test (P = 0.002). Similarly visually assessed angiographic stenosis showed a significant increase in the restenotic group (8.6 +/- 0.56 vs. 8.0 +/- 0.61 fl, P = 0.001). The relative odds for developing clinically defined restenosis were 10.2 times greater if the pre-procedural MPV lay in the upper compared to the lowest quartile. There was a positive correlation between MPV and change in minimal luminal diameter between post angioplasty and follow-up angiography, assessed quantitatively, r = +0.56, P = 0.016. There was no association between clinical or angiographic definitions of restenosis and haemoglobin, red cell count, mean corpuscular volume, white cell count or platelet count. Platelet size may influence the development of restenosis after successful coronary angioplasty.

Left atrial spontaneous echo contrast assessed by TEE in patients with either native mitral valve disease or mitral valve replacement.

The incidence of spontaneous echo contrast in the left atrium, the factors with which it is associated, and its clinical significance were studied in 128 patients with native mitral valve disease or mitral valve replacement. All patients underwent both transesophageal and transthoracic echocardiography. Spontaneous echo contrast was visualized in 42 patients (33%) during transesophageal and in none during transthoracic echocardiography. Patients with spontaneous echo contrast had a significantly larger left atrial diameter (6.1 [1.1] cm vs 4.9 [0.9] cm, p < 0.001) and a greater incidence of both atrial fibrillation (54% vs 4%, p < 0.001) and left atrial thrombi (60% vs 28%, p < 0.01) compared with patients without spontaneous echo contrast. Multivariant analysis confirmed that these factors were independently associated with spontaneous echo contrast (left atrial size, p < 0.001; atrial fibrillation, p < 0.001; left atrial thrombus, p < 0.01). Patients with pure mitral regurgitation did not have any spontaneous echo contrast and anticoagulation did not influence its incidence. Spontaneous echo contrast was the only factor that was associated with a previous history of systemic embolization (history of systemic emboli in 28.6% of patients with spontaneous echo contrast vs 13.9% without spontaneous echo contrast, p < 0.05). In conclusion, spontaneous echo contrast is a common finding in the left atrium of patients with mitral valve disease or mitral valve replacement and represents a marker of increased thromboembolic risk in these patients.

Left ventricle filling abnormalities prior to and following treatment of thyrotoxicosis--is diastolic dysfunction implicated in thyrotoxic cardiomyopathy?

Despite cardiac failure being a well recognised complication of thyrotoxicosis, systolic function has generally been reported as maintained or enhanced. In this study, left ventricular diastolic function was assessed in 16 thyrotoxic patients and 18 age-matched controls by pulsed-Doppler echocardiography. Patients were re-studied after 3 and 12 months of treatment. Prior to treatment all standard Doppler-derived indices of diastolic function were significantly different to control (isovolumic relaxation time (IVRT) 63 +/- 18.9 vs 84.0 +/- 14.8 ms, peak early filling velocity (Emax) 79.2 +/- 15.2 vs 61.9 +/- 10.7 cm.s-1, peak atrial filling velocity (Amax) 68.2 +/- 17.9 vs 42.2 +/- 9.4 cm.s-1, deceleration of early filling (E/F slope) 6.1 +/- 1.8 vs 3.7 +/- 1.1 m.s-1, thyrotoxic vs control). However, these filling abnormalities appear likely to reflect the tachycardia and reduced systemic vascular resistance (SVR) found in the patients (heart rate 102 +/- 15 vs 76 +/- 9, SVR 874 +/- 207 vs 1293 +/- 362 dynes.s-1 x cm-5, both P < 0.001). After 3 months of treatment haemodynamics were similar in the two groups but filling remained abnormal in patients with a pattern suggesting increased transmitral pressure gradients (Emax 73.1 +/- 15.1 cm.s-1, Amax 55.8 +/- 19.2 cm.s-1, E/F slope 4.9 +/- 2.0 m.s-1, all P < 0.05 compared to controls).(ABSTRACT TRUNCATED AT 250 WORDS)

Echocardiographic restenosis after successful balloon dilatation of the mitral valve with the Inoue balloon: experience of a United Kingdom centre.

OBJECTIVES: (a) To assess the echocardiographic incidence of restenosis after successful balloon dilatation of the mitral valve at a mid-term follow up of one year among a population of predominantly United Kingdom patients. (b) To identify any factors, assessed before or during dilatation, which may predict the development of restenosis. DESIGN: Successful dilatation of the mitral valve was defined as an increase in mitral valve area of > 25% and a final valve area of at least 1.5 cm2. Echocardiographic restenosis was defined at follow up as a loss of 50% of initial gain and a valve area of less than 1.5 cm2. Mitral valve area was assessed by transthoracic echocardiography before, during, 48 hours after, and one year after successful balloon dilatation of the mitral valve. Echo score before dilatation (an assessment of valvar and subvalvar calcification, thickening, and mobility), age, rhythm, echocardiographic mitral valve area before and after dilatation, left atrial pressure before and after dilatation, and end diastolic mitral valve gradient before and after dilatation were compared in those patients with and without echocardiographic restenosis at one year. SETTING: A regional cardiothoracic centre in the United Kingdom that performs 20-30 balloon dilatations of mitral valves each year. PATIENTS: 39 patients, with symptomatic dominant mitral stenosis, who had undergone successful balloon dilatation of the mitral valve, and in whom echocardiographic assessment of mitral valve area was available at one year. 92% of patients were citizens of the United Kingdom. INTERVENTIONS: Balloon dilatation of the mitral valve by the Inoue technique. MAIN OUTCOME MEASURES: Mitral valve area and patient symptom class (New York Heart Association) one year after successful dilatation of the mitral valve. RESULTS: The incidence of echocardiographic restenosis was eight of 39 patients (21%). Of the eight patients with restenosis four underwent mitral valve replacement, two had repeat dilatation of the mitral valve, and two remained on medical treatment. With univariant analysis, factors associated with restenosis were increased age, higher echo score before dilatation, and a lower mitral valve area immediately after the operation. The only independent risk factor for restenosis, shown by multivariant analysis, was a high echo score before dilatation. There was no significant fall in mitral valve area at one year in those patients without restenosis. Most (28/31) of these patients had echocardiographic evidence of splitting of at least one commissure after dilatation compared with only two of eight patients who developed restenosis. Of 10 patients with an echo score before dilatation > or = 10 only two had an initially successful operation and no restenosis at one year. CONCLUSIONS: The echocardiographic incidence of restenosis after dilatation of the mitral valve by the Inoue technique in patients of the United Kingdom is 21%. The principal factor associated with restenosis is a high echo score before dilatation. Increases in mitral valve area are maintained in those patients without restenosis and it is likely that the mechanism of initial increase in valve area is different in the two groups, being commissural splitting in those patients who do not get restenosis and valve stretching in those that do. In patients with an echo score > or = 10 dilatation of the mitral valve should be considered only as a palliative procedure.