Tissue characteristics of restenosis after percutaneous transluminal coronary angioplasty in diabetic patients

OBJECTIVES

The purposes of this study were to analyze coronary specimens from patients with diabetes mellitus (DM) and to compare them with specimens from patients without DM.

BACKGROUND

Diabetes mellitus is associated with an increased incidence of restenosis after percutaneous transluminal coronary angioplasty (PTCA). Increased hypercellular smooth muscle cell proliferation with exaggerated intimal hyperplasia formation may be responsible for this predisposition.

METHODS

Eighteen coronary atherectomy specimens with restenosis after PTCA from patients with DM were compared with 18 coronary atherectomy specimens with restenosis after PTCA from patients without DM. Total and segmental areas were quantified on trichrome-stained tissue of hypercellular tissue, collagen-rich sclerotic tissue, atheroma and thrombus. Demographic and angiographic data were similar in both groups.

RESULTS

The percentage of total plaque area composed of hypercellular tissue was lower in restenotic specimens from patients with DM than in restenotic specimens from patients without DM (19 +/- 6% vs. 44 +/- 5%; p = 0.003). The percentage of collagen-rich sclerotic tissue area was larger in restenotic specimens from patients with DM than in restenotic specimens from patients without DM (77 +/- 9% vs. 53 +/- 4%; p = 0.004). The percentages of atheroma and thrombus were similar in both groups.

CONCLUSIONS

Intimal hypercellular tissue content is reduced in restenotic tissue from patients with DM. Collagen-rich sclerotic content is increased in restenotic lesions from patients with DM. These results suggest an accelerated fibrotic rather than a proliferative response in diabetic lesions from patients with restenosis after PTCA.

Mitral balloon valvotomy for patients with mitral stenosis in atrial fibrillation: immediate and long-term results

OBJECTIVES

The purpose of this study was to examine the effect of atrial fibrillation (AF) on the immediate and long-term outcome of patients undergoing percutaneous mitral balloon valvuloplasty (PMV).

BACKGROUND

There is controversy as to whether the presence of AF has a direct negative effect on the outcome after PMV.

METHODS

The immediate procedural and the long-term clinical outcome after PMV of 355 patients with AF were prospectively collected and compared with those of 379 patients in normal sinus rhythm (NSR).

RESULTS

Patients with AF were older (62 +/- 12 vs. 48 +/- 14 years; p < 0.0001) and presented more frequently with New York Heart Association (NYHA) class IV (18.3% vs. 7.9%; p < 0.0001), echocardiographic score >8 (40.1% vs. 25.1%; p < 0.0001), calcified valves under fluoroscopy (32.4% vs. 18.8%, p < 0.0001) and with history of previous surgical commissurotomy (21.7% vs. 16.4%; p = 0.0002). In patients with AF, PMV resulted in inferior immediate and long-term outcomes, as reflected in a smaller post-PMV mitral valve area (1.7 +/- 0.7 vs. 2 +/- 0.7 cm2; p < 0.0001) and a lower event free survival (freedom of death, redo-PMV and mitral valve surgery) at a mean follow-up time of 60 months (32% vs. 61%; p < 0.0001). In the group of patients in AF, severe post-PMV mitral regurgitation (> or =3+) (p = 0.0001), echocardiographic score >8 (p = 0.004) and pre-PMV NYHA class IV (p = 0.046) were identified as independent predictors of combined events at follow-up.

CONCLUSIONS

Patients with AF have a worse immediate and long-term outcomes after PMV. However, the presence of AF by itself does not unfavorably influence the outcome, but is a marker for clinical and morphologic features associated with inferior results after PMV.

Histopathologic comparison of human coronary in-stent and post-balloon angioplasty restenotic tissue

Histomorphometric studies for smooth muscle cells, macrophages, tissue factor, collagen, and cell proliferation were performed on 20 atherectomy specimens from patients with in-stent restenosis and 20 specimens from patients with post-balloon PTCA restenosis. Smooth muscle cell content was larger and proliferation index was higher in in-stent restenotic tissue; macrophage, tissue factor, and collagen content were larger in post-balloon percutaneous transluminal coronary angioplasty restenotic tissue, suggesting a more cellular and proliferative response with less thrombogenic potential in human tissue from in-stent restenosis than tissue from post-balloon percutaneous transluminal coronary angioplasty restenosis.

Ventricular remodeling in active myocarditis. Myocarditis Treatment Trial

BACKGROUND

Remodeling of the left ventricle with the development of a spherical cavity occurs in dilated cardiomyopathy and is associated with a poor long-term prognosis. The early effects of myocarditis on left ventricular geometry have not been previously described or correlated with clinical outcome.

METHODS

The baseline echocardiograms of 35 patients with biopsy-confirmed myocarditis were compared with 20 normal controls. Left ventricular end-diastolic volume, long axis length, and mid-cavity diameter were measured. The degree of sphericity was expressed as the ratio of the mid-cavity diameter to the long axis length. Left ventricular ejection fraction was assessed by radionuclide angiography.

RESULTS

In patients with myocarditis, mean left ventricular volume of 81 +/- 29 mL/m(2) was significantly greater than 50 +/- 8 mL/m(2) in controls (P =.001). Chamber dilatation occurred primarily along the mid-cavity diameter, which measured 5.3 +/- 0.8 cm in patients with myocarditis versus 4.2 +/- 0.4 cm in controls (P =.001). The degree of left ventricular sphericity in patients with myocarditis, 0.64 +/- 0.08, was significantly greater than that of controls, 0.54 +/- 0.04 (P =.001). When patients were stratified according to left ventricular volume, patients with increased left ventricular volume (>75 mL/m(2)) were associated with a more spherical chamber and lower left ventricular ejection fraction than patients with a more normal left ventricular volume (</=75 mL/m(2)).

CONCLUSIONS

Active myocarditis is associated with early left ventricular remodeling and the development of a spherical chamber. These changes correlate with ventricular dilatation and reduced left ventricular ejection fraction.

Implications of small reference vessel diameter in patients undergoing percutaneous coronary revascularization

OBJECTIVES

The purpose of this study was to determine whether small reference diameter of the culprit coronary artery influences the outcome of an attempted percutaneous revascularization procedure in the current era of interventional cardiology.

BACKGROUND

Although the interventional strategy is largely determined by the size of the culprit coronary artery, earlier quantitative studies have not shown a worse acute outcome for small reference vessel diameter (< or =2.5 mm).

METHODS

A total of 2,306 patients undergoing percutaneous coronary revascularization was divided in groups with reference diameters < or =2.5 mm (n = 813) or >2.5 mm (n = 1,493). Success and in-hospital major adverse cardiac event (death, Q-wave myocardial infarction and emergency coronary artery bypass graft) rates between both groups were compared.

RESULTS

Patients with lesions in small vessels were older and presented more frequently with female gender, diabetes mellitus, heart failure, peripheral vascular, multivessel coronary disease and American Heart Association/American College of Cardiology (AHA/ACC) lesion type C (p < or = 0.01, each). Further, utilization of interventional devices differed markedly. In contrast to stents (18.5% vs. 41.9%) and directional atherectomy (3.7% vs. 13.5%), conventional balloon angioplasty (73% vs. 50%) and rotational atherectomy (16.1% vs. 8.3%) were used more often in smaller vessels (p < or = 0.0001, each). Success rate was lower in the small vessel group (92% vs. 95%; p = 0.006). Major adverse cardiac events occurred more frequently in small than large vessels (univariate 3.4% vs. 2.0%, p = 0.03; multivariate odds ratio 2.1, p = 0.02), particularly when proximal coronary segments were compared.

CONCLUSIONS

Lesions in vessels with small reference diameter represent a distinct group with respect to clinical and morphologic characteristics as well as device utilization. These lesions have lower chances of successful percutaneous intervention and carry relatively higher risks, specifically when located in proximal coronary segments.

Is redo percutaneous mitral balloon valvuloplasty (PMV) indicated in patients with post-PMV mitral restenosis?

OBJECTIVES

The purpose of this study was to assess the immediate and long-term outcome of repeat percutaneous mitral balloon valvuloplasty (PMV) for post-PMV mitral restenosis.

BACKGROUND

Symptomatic mitral restenosis develop in 7% to 21% of patients after PMV. Currently, most of these patients are referred for mitral valve replacement. However, it is unknown if these patients may benefit from repeat PMV.

METHODS

We report the immediate outcome and long-term clinical follow-up results of 36 patients (mean age 58+/-13 years, 75% women) with symptomatic mitral restenosis after prior PMV, who were treated with a repeat PMV at 34.6+/-28 months after the initial PMV. The mean follow-up period was 30+/-33 months with a maximal follow-up of 10 years.

RESULTS

An immediate procedural success was obtained in 75% patients. The overall survival rate was 74%, 72% and 71% at one, two, and three years respectively. The event-free survival rate was 61%, 54% and 47% at one, two, and three years respectively. In the presence of comorbid diseases (cardiac and noncardiac) the two-year event-free survival was reduced to 29% as compared with 86% in patients without comorbid diseases. Cox regression analysis identified the echocardiographic score (p = 0.03), post-PMV mitral valve area (p = 0.003), post-PMV mitral regurgitation grade (p = 0.02) and post-PMV pulmonary artery pressure (p = 0.0001) as independent predictors of event-free survival after repeat PMV.

CONCLUSIONS

Repeat PMV for post-PMV mitral restenosis results in good immediate and long-term outcome in patients with low echocardiographic scores and absence of comorbid diseases. Although the results are less favorable in patients with suboptimal characteristics, repeat PMV has a palliative role if the patients are not surgical candidates.

Pericardial Effusion and Tamponade

Pericardial effusion may occur as a result of a variety of clinical conditions, including viral, bacterial, or fungal infections and inflammatory, postinflammatory, autoreactive, and neoplastic processes. More common causes of pericardial effusion and tamponade include malignancy, renal failure, viral and bacterial infectious processes, radiation, aortic dissection, and hypothyroidism. It can also occur after trauma or acute myocardial infarction (as in postpericardiotomy syndrome following cardiac or thoracic surgery) or as an idiopathic pericardial effusion. Although pericardial effusion is common in patients with connective tissue disease, cardiac tamponade is rare. Among medical patients, malignant disease is the most common cause of pericardial effusion with tamponade. Table 1 shows the causes of pericardial tamponade. The effusion fluid may be serous, suppurative, hemorrhagic, or serosanguineous. The pericardial fluid can be a transudate (typically occurring in patients with congestive heart failure) or an exudate. The latter type, which contains a high concentration of proteins and fibrin, can occur with any type of pericarditis, severe infections, or malignancy. Once the diagnosis of pericardial effusion has been made, it is important to determine whether the effusion is creating significant hemodynamic compromise. Asymptomatic patients without hemodynamic compromise, even with large pericardial effusions, do not need to be treated with pericardiocentesis unless there is a need for fluid analysis for diagnostic purposes (eg, in acute bacterial pericarditis, tuberculosis, and neoplasias). The diagnosis of pericardial effusion/tamponade relies on a strong clinical suspicion and is confirmed by echocardiography or other pericardial imaging modalities. Alternatively, when the diagnosis of cardiac tamponade is made, there is a need for emergency drainage of pericardial fluid by pericardiocentesis or surgery to relieve the hemodynamic compromise. Following pericardiocentesis, it is necessary to prevent recurrence of tamponade. Intrapericardial injection of sclerosing agents, surgical pericardiotomy, and percutaneous balloon pericardial window creation are techniques used to prevent reaccumulation of pericardial fluid and recurrence of cardiac tamponade.

Comparison of immediate and long-term results of mitral balloon valvotomy with the double-balloon versus Inoue techniques

There is controversy as to whether the double-balloon or Inoue technique of percutaneous mitral balloon valvotomy (PMBV) provides superior immediate and long-term results. This study compares the immediate procedural and long-term outcomes of patients undergoing PMBV using the double-balloon versus the Inoue techniques. Seven hundred thirty-four consecutive patients who underwent PMBV using the double-balloon (n = 621) or Inoue technique (n = 113) were studied. There were no statistically significant differences in baseline clinical and morphologic characteristics between the double-balloon and Inoue patients. The double-balloon technique resulted in superior immediate outcome, as reflected in a larger post-PMBV mitral valve area (1.9 +/- 0.7 vs 1.7 +/- 0.6 cm2; p = 0.005) and a lower incidence of 3+ mitral regurgitation after PMBV (5.4% vs 10.6%; p = 0.05). This superior immediate outcome of the double-balloon technique was observed only in the group of patients with echocardiographic score < or = 8 (post-PMBV mitral valve areas 2.1 +/- 0.7 vs 1.8 +/- 0.6; p = 0.004). Despite the difference in immediate outcome, there were no significant differences in event-free survival at long-term follow-up between the 2 techniques. Our study demonstrates that compared with the Inoue technique, the double-balloon technique results in a larger mitral valve area and less degree of severe mitral regurgitation after PMBV. Despite the difference in immediate outcome between both techniques, there were no significant differences in event-free survival at long-term follow-up.

Echocardiography can predict the development of severe mitral regurgitation after percutaneous mitral valvuloplasty by the Inoue technique

Severe mitral regurgitation (MR) following mitral balloon valvuloplasty is a major complication of this procedure. We recently described a new echocardiographic score that can predict the development of severe MR following mitral valvuloplasty with the double balloon technique. The present study was designed to test the usefulness of this score for predicting severe MR in patients undergoing the procedure using the Inoue balloon technique. From 117 consecutive patients who underwent mitral valvuloplasty using the Inoue technique, 14 (11.9%) developed severe MR after the procedure. A good quality echocardiogram before mitral valvuloplasty was available in 11 patients. These 11 patients were matched by age, sex, mitral valve area, and degree of MR before valvuloplasty with 69 randomly selected patients who did not develop severe MR after Inoue valvuloplasty. The total MR-echocardiographic (MR-echo) score was significantly greater in the severe MR group (10.5 +/- 1.4 vs 8.2 +/- 1.1; p <0.001). In addition, the component grades for the anterior leaflet (2.9 +/- 0.5 vs 2.2 +/- 0.4; p <0.001), posterior leaflet (2.6 +/- 0.7 vs 1.9 +/- 0.8), commissures (2.4 +/- 0.8 vs 2.0 +/- 0.5; p <0.05) and subvalvular apparatus (2.6 +/- 0.5 vs 1.9 +/- 0.4; p <0.001) were also higher in the MR group. Using a total score of > or = 10 as a cut-off point for predicting severe MR with the Inoue technique, a sensitivity of 82%, specificity of 91%, accuracy of 90%, and negative predictive value of 97% were obtained. Stepwise logistic regression analysis identified the MR-echo score as the only independent predictor for developing severe MR with the Inoue technique (p <0.0001). Thus, the MR-echo score can also predict the development of severe MR following mitral balloon valvuloplasty using the Inoue technique.

Directional coronary atherectomy for the treatment of Palmaz-Schatz in-stent restenosis

Management of in-stent restenosis has become a significant challenge in interventional cardiology. The results of balloon angioplasty have been disappointing due to the high recurrence of restenosis at follow-up. Debulking of the restenotic tissue within the stents using directional coronary atherectomy (DCA) may offer a therapeutic advantage. We report the immediate clinical and angiographic outcomes and long-term clinical follow-up results of 45 patients (46 lesions), mean age 63+/-12 years, 73% men, with a mean reference diameter of 2.9+/-0.6 mm, treated with DCA for symptomatic Palmaz-Schatz in-stent restenosis. DCA was performed successfully in all 46 lesions and resulted in a postprocedural minimal luminal diameter of 2.7+/-0.7 mm and a residual diameter stenosis of 17+/-10%. There were no in-hospital deaths, Q-wave myocardial infarctions, or emergency coronary artery bypass surgeries. Four patients (9%) suffered a non-Q-wave myocardial infarction. Target lesion revascularization was 28.3% at a mean follow-up of 10+/-4.6 months. Kaplan-Meier event-free survival (freedom from death, myocardial infarction, and repeat target lesion revascularization) was 71.2% and 64.7% at 6 and 12 months after DCA, respectively. Thus, DCA is safe and efficacious for the treatment of Palmaz-Schatz in-stent restenosis. It results in a large postprocedural minimal luminal diameter and a low rate of both target lesion revascularization and combined major clinical events at follow-up.

Histopathology of coronary lesions with early loss of minimal luminal diameter after successful percutaneous transluminal coronary angioplasty: is thrombus a significant contributor?

BACKGROUND

Early loss of minimal luminal diameter of >0.3 mm after successful percutaneous transluminal coronary angioplasty (PTCA) is associated with a higher incidence of restenosis. The underlying mechanism of this early loss is unknown and thrombus may be a contributing factor.

METHODS

We performed a prospective study using quantitative computerized planimetry on coronary tissue specimens obtained by directional coronary atherectomy of 24 lesions in which early loss occurred 22+/-9 minutes after successful PTCA.

RESULTS

Thrombus was present in 9 (37%) of 24 coronary specimens. Segmental areas (mm2) and percentage of total area were distributed as follows: sclerotic tissue, 4.07+/-0.7 mm2 (63%+/-6%); fibrocellular tissue, 0.97+/-0.27 mm2 (16%+/-4%); hypercellular tissue, 0.99+/-0.29 mm2 (12%+/-3%); atheromatous gruel, 0.18+/-0.07 mm2 (3%+/-0.1%); and thrombus, 0.24+/-0.15 mm2 (6%+/-0.4%). There was no difference in the relative early loss index between lesions with or without thrombus (35%+/-7% vs 26%+/-2%, respectively; P= .87). Multiple stepwise regression analysis did not identify any histologic predictors of relative early loss index.

CONCLUSION

Histopathologic analysis of coronary lesions with early loss after successful PTCA suggests that thrombus may not play a significant role in this angiographic phenomenon.

Optimal coronary balloon angioplasty with provisional stenting versus primary stent (OCBAS): immediate and long-term follow-up results

OBJECTIVE

This study sought to compare two strategies of revascularization in patients obtaining a good immediate angiographic result after percutaneous transluminal coronary angioplasty (PTCA): elective stenting versus optimal PTCA. A good immediate angiographic result with provisional stenting was considered to occur only if early loss in minimal luminal diameter (MLD) was documented at 30 min post-PTCA angiography.

BACKGROUND

Coronary stenting reduces restenosis in lesions exhibiting early deterioration (>0.3 mm) in MLD within the first 24 hours (early loss) after successful PTCA. Lesions with no early loss after PTCA have a low restenosis rate.

METHODS

To compare angiographic restenosis and target vessel revascularization (TVR) of lesions treated with coronary stenting versus those treated with optimal PTCA, 116 patients were randomized to stent (n=57) or to optimal PTCA (n=59). After randomization in the PTCA group, 13.5% of the patients crossed over to stent due to early loss (provisional stenting).

RESULTS

Baseline demographic and angiographic characteristics were similar in both groups of patients. At 7.6 months, 96.6% of the entire population had a follow-up angiographic study: 98.2% in the stent and 94.9% in the PTCA group. Immediate and follow-up angiographic data showed that acute gain was significantly higher in the stent than in the PTCA group (1.95 vs. 1.5 mm; p < 0.03). However, late loss was significantly higher in the stent than the PTCA group (0.63+/-0.59 vs. 0.26+/-0.44, respectively; p=0.01). Hence, net gain with both techniques was similar (1.32< or =0.3 vs. 1.24+/-0.29 mm for the stent and the PTCA groups, respectively; p=NS). Angiographic restenosis rate at follow-up (19.2% in stent vs. 16.4% in PTCA; p=NS) and TVR (17.5% in stent vs. 13.5% in PTCA; p=NS) were similar. Furthermore, event-free survival was 80.8% in the stent versus 83.1% in the PTCA group (p=NS). Overall costs (hospital and follow-up) were US $591,740 in the stent versus US $398,480 in the PTCA group (p < 0.02).

CONCLUSIONS

The strategy of PTCA with delay angiogram and provisional stent if early loss occurs had similar restenosis rate and TVR, but lower cost than primary stenting after PTCA.

Coronary endothelial dysfunction in patients with acute-onset idiopathic dilated cardiomyopathy

OBJECTIVES

This study sought to determine whether coronary endothelial dysfunction exists in patients with acute-onset idiopathic dilated cardiomyopathy (DCM) and to explore its relation to recovery of left ventricular systolic function in this patient population.

BACKGROUND

Coronary endothelial dysfunction exists in chronic DCM, but its importance in the development and progression of ventricular dysfunction is not known. To address this issue we studied coronary endothelial function in patients with idiopathic DCM <6 months in duration and explored the relation between coronary endothelial function and subsequent changes in left ventricular ejection fraction (LVEF).

METHODS

Ten patients with acute-onset idiopathic DCM (duration of heart failure symptoms 2.0 +/- 0.4 months [mean +/- SEM]) and 11 control patients with normal left ventricular function underwent assessment of coronary endothelial function during intracoronary administration of the endothelium-dependent vasodilator acetylcholine and the endothelium-independent vasodilator adenosine. Coronary cross-sectional area (CSA) was determined by quantitative coronary angiography and coronary blood flow (CBF) by the product of coronary CSA and CBF velocity measured by an intracoronary Doppler catheter. Patients with DCM underwent assessment of left ventricular function before and several months after the study.

RESULTS

Acetylcholine infusion produced no change in coronary CSA in control patients but significant epicardial constriction in patients with DCM (-36 +/- 11%, p < 0.01). These changes were associated with increases in CBF in control patients (+118 +/- 49%, p < 0.01) but no change in patients with DCM. Infusion of adenosine produced increases in coronary caliber and blood flow in both groups. Follow-up assessment of left ventricular function was obtained in nine patients with DCM 7.0 +/- 1.7 months after initial study, at which time LVEF had improved by > or =0.10 in four patients. Multiple linear regression revealed a positive correlation between both the coronary CSA (r2 = 0.57, p < 0.05) and CBF (r2 = 0.68, p < 0.01) response to acetylcholine and the subsequent improvement in LVEF.

CONCLUSIONS

Coronary endothelial dysfunction exists at both the microvascular and the epicardial level in patients with acute-onset idiopathic DCM. The preservation of coronary endothelial function in this population is associated with subsequent improvement in left ventricular function.

Comparison of primary coronary stenting to primary balloon angioplasty with stent bailout for the treatment of patients with acute myocardial infarction

This study compares the immediate and long-term outcomes of a primary coronary stenting strategy with primary balloon angioplasty with stent bailout in the treatment of patients with acute myocardial infarction (AMI). One hundred forty-seven consecutive patients who underwent primary balloon angioplasty with stent bailout (n = 94) or primary stenting (n = 53) for AMI were clinically followed for 8.1 +/- 5.7 and 8.5 +/- 4.5 months, respectively. Immediate results, as well as in-hospital and long-term ischemic events (death, reinfarction, and repeat revascularization) were compared between both groups. Angiographic success was 91.5% in the balloon angioplasty group and 94% in the stent group. In-hospital and late follow-up combined ischemic events were 22 of 94 (23%) versus 0 of 53 (0%); p < 0.001 and 33 of 78 (42%) versus 13 of 53 (25%), p = 0.04 for the balloon angioplasty and stent groups, respectively. At 6 months, the cumulative probability of repeat target lesion revascularization was higher in the balloon angioplasty group (47% vs 18%, p = 0.0006) as was the probability of late target revascularization (36% vs 18%, p = 0.046); the cumulative event-free survival after 6 months was significantly lower in the balloon angioplasty group (44% vs 80%, p = 0.0001). This study demonstrates that a primary stent placement strategy in patients with AMI is safe, feasible, and superior to primary balloon angioplasty with stent bailout. Primary stenting results in a larger postprocedural minimal luminal diameter, a lower early and late recurrent ischemic event rate, and a lower incidence of target lesion revascularization at follow-up.

Continuous quality improvement decreases length of stay and adverse events: a case study in an interventional cardiology program

A study was performed to assess the effectiveness of continuous quality improvement in achieving a better quality of care for patients undergoing coronary interventions. Increasing utilization of new coronary interventional devices has incurred a higher incidence of complications, prolonged hospital stay, and related costs. Using a clinical information system, we adopted continuous quality improvement to control the incidence of complications and postprocedural length of stay. Multiple regression analysis and a matched case-control study were performed to detect complications related to postprocedural length of stay and their causes among 342 patients. The results led to the modification of the postprocedural heparin anticoagulation protocol, which was followed by the introduction of a ticlopidine-based poststent anticoagulation regimen. Two sequential groups of patients (n = 261, n = 266) were selected to compare postprocedural length of stay and frequency of complications with those for the first group. Adjustments were made for patients and procedural characteristics through stratification and multiple regression methods. Blood transfusion was the most important predictor of prolonged hospital stay (partial R2 = 0.26, P < 0.01). A high level of postprocedural anticoagulation and intracoronary stent use were significantly associated with blood transfusion (P = 0.01, P = 0.02, respectively). The comparison among the three groups showed that heparin protocol change reduced only postprocedural length of stay (P < 0.001) for patients without stents, whereas the stent change in anticoagulation protocol significantly reduced both transfusion and hospital stay for patients with stents (P < 0.001, P < 0.05, respectively). Continuous quality improvement based on clinical information is promising to control both complications and hospital costs. Physician involvement is necessary throughout the process.

Restoration of coronary flow in myocardial infarction by intravenous chimeric 7E3 antibody without exogenous plasminogen activators. Observations in animals and humans

BACKGROUND

Coronary thrombus is composed of platelets and fibrin, and during thrombolytic treatment, reflow may be slowed by platelet deposition. It may be possible to initiate coronary reflow without exogenous plasminogen activators by blocking platelet aggregation while fibrin generation is impeded with heparin.

METHODS AND RESULTS

In 14 dogs, left anterior descending coronary artery thrombosis was produced by endothelial trauma and thrombin instillation in the presence of stenosis distally. Reflow was monitored by flow probe during treatment with (1) heparin, (2) heparin and aspirin, and (3) heparin, aspirin, and intravenous 7E3. Eighty percent of dogs treated with the third combination showed stable reflow (> or = 25% of prestenotic flow) in 50 +/- 9 minutes. In addition, 13 patients were studied during intravenous administration of c7E3 10 minutes before primary angioplasty for acute myocardial infarction and Thrombolysis In Myocardial Infarction (TIMI) grade 0 or 1 flow. Pretreatment included heparin and oral aspirin. Flow increased during a 10-minute period by at least one TIMI grade in 11 (85%) of 13 and reached TIMI grade 2 or 3 in 7 (54%) of 13 patients. Average TIMI grade flow increased from 0.31 +/- 0.5 to 1.54 +/- 0.8 (P < .001). Thrombus length 10 minutes after c7E3 was 5.1 +/- 3.5 mm. All but 1 patient then underwent angioplasty. There were no complications.

CONCLUSIONS

Coronary reflow can be initiated by intravenous 7E3 administration in the presence of heparin and aspirin. In human patients, this flow can be observed in 10 minutes without exogenous thrombolytic agents.

Comparison of the usefulness of Doppler pressure half-time in mitral stenosis in patients < 65 and > or = 65 years of age

Doppler pressure half-time is a reliable method for estimating mitral valve area when net left atrial and ventricular compliance remain stable. The accuracy of Doppler pressure half-time in estimating mitral valve area in older patients is unknown. We studied 80 patients (65 women and 15 men, aged 56 +/- 14 years) with cardiac catheterization and echocardiography. Mitral valve area was calculated using the Gorlin formula and by the Doppler pressure half-time method. Patients were stratified into those aged < 65 years (n = 57), and those aged > or = 65 years (n = 23). The discordance between pressure half-time and Gorlin-derived mitral valve area was assessed and related to multiple clinical, echocardiographic, and hemodynamic variables. The difference between pressure half-time and Gorlin-derived mitral valve area was greater in the older than in the younger patient (0.34 +/- 0.30 vs 0.15 +/- 0.27 cm2, p = 0.009) but the older group had smaller mitral valve areas by the Gorlin method (0.72 +/- 0.18 vs 0.89 +/- 0.32 cm2, p = 0.02) and lower cardiac output. The difference between pressure half-time and Gorlin remained greater in the group of older patients (0.32 +/- 0.30 vs 0.19 +/- 0.22 cm2, p = 0.04), even when the analysis was restricted to patients with similar mitral valve area (< 1 cm2 by the Gorlin method). Using multivariate analysis, age > or = 65 years remained the only significant predictor of the discrepancy between pressure half-time and Gorlin mitral valve area. Thus, when compared with Gorlin-derived mitral valve area, pressure half-time overestimated valve area in older patients, and this technique for estimating mitral valve area should be used with caution in patients > or = 65 years of age.

Macrophage infiltration predicts restenosis after coronary intervention in patients with unstable angina

BACKGROUND

Restenosis remains the major limitation of percutaneous coronary revascularization. Macrophages release cytokines, metalloproteinases, and growth factors that may induce smooth muscle cell migration and proliferation. We tested the hypothesis that primary lesions that develop restenosis after coronary atherectomy have more macrophages and smooth muscle cells than primary lesions that do not develop restenosis.

METHODS AND RESULTS

Fifty patients with unstable angina were identified. Total and segmental areas were quantified on trichrome-stained sections of coronary atherectomy tissue. Macrophages and smooth muscle cells were identified by immunohistochemical staining. Restenosis, defined as > 50% stenosis diameter by quantitative cineangiography, was present in 30 patients. The other 20 patients (< 50% stenosis) constitute the "no restenosis" group. The percentages of smooth muscle cell areas were similar in specimens from patients with and without restenosis (57 +/- 5% and 52 +/- 6%) (P = NS). However, macrophage-rich areas were larger in plaque tissue from patients with restenosis (20.4 +/- 2%) than in tissue from patients without restenosis (9.3 +/- 2%) (P = .0007). Multiple stepwise logistic regression analysis identified macrophages as the only independent predictor for restenosis (P = .006).

CONCLUSIONS

Macrophages are increased in coronary atherectomy tissue from primary lesions that develop restenosis, suggesting a possible role for macrophages in the restenotic process after percutaneous coronary intervention.

Macrophages, smooth muscle cells, and tissue factor in unstable angina. Implications for cell-mediated thrombogenicity in acute coronary syndromes

BACKGROUND

Macrophage expression of tissue factor may be responsible for coronary thrombogenicity in patients with plaque rupture. In patients without plaque rupture, smooth muscle cells may be the thrombogenic substrate. This study was designed to identify the cellular correlations of tissue factor in patients with unstable angina.

METHODS AND RESULTS

Tissue from 50 coronary specimens (1560 pieces) from patients with unstable angina and 15 specimens from patients with stable angina were analyzed. Total and segmental areas (in square millimeters) were identified with trichrome staining. Macrophages, smooth muscle cells, and tissue factor were identified by immunostaining. Tissue factor content was larger in unstable angina (42 +/- 3%) than in stable angina (18 +/- 4%) (P = .0001). Macrophage content was also larger in unstable angina (16 +/- 2%) than in stable angina (5 +/- 2%) (P = .002). The percentage of tissue factor located in cellular areas was larger in coronary samples from patients with unstable angina (67 +/- 8%) than in samples from patients with stable angina (40 +/- 5%) (P = .00007). Multiple linear stepwise regression analysis showed that coronary tissue factor content correlated significantly (r = .83, P < .0001) with macrophage and smooth muscle cell areas only in tissue from patients with unstable angina, with a strong relationship between tissue factor content and macrophages in the atheromatous gruel (r = .98, P < .0001).

CONCLUSIONS

Tissue factor content is increased in unstable angina and correlates with areas of macrophages and smooth muscle cells, suggesting a cell-mediated thrombogenicity in patients with acute coronary syndromes.

Four-year follow-up of patients undergoing percutaneous balloon mitral commissurotomy. A report from the National Heart, Lung, and Blood Institute Balloon Valvuloplasty Registry

OBJECTIVES

This study reports the long-term outcome of patients undergoing percutaneous balloon mitral commissurotomy who were enrolled in the National Heart, Lung, and Blood Institute (NHLBI) Balloon Valvuloplasty Registry.

BACKGROUND

The NHLBI established the multicenter Balloon Valvuloplasty Registry in November 1987 to assess both short- and long-term safety and efficiency of percutaneous balloon mitral commissurotomy.

METHODS

Between November 1987 and October 1989, 736 patients > or = 18 years old underwent percutaneous balloon mitral commissurotomy at 23 registry sites in North America. The maximal follow-up period was 5.2 years.

RESULTS

The actuarial survival rate was 93 +/- 1% (mean +/- SD), 90 +/- 1.2%, 87 +/- 1.4% and 84 +/- 1.6% at 1, 2, 3 and 4 years, respectively. Eighty percent of the patients were alive and free of mitral surgery or repeat balloon mitral commissurotomy at 1 year. The event-free survival rate was 80 +/- 1.5% at 1 year, 71 +/- 1.7% at 2 years, 66 +/- 1.8% at 3 years and 60 +/- 2.0% at 4 years. Important univariable predictors of actuarial mortality at 4 years included age > 70 years (51% survival), New York Heart Association functional class IV (41% survival) and baseline echocardiographic score > 12 (24% survival). Multivariable predictors of mortality included functional class IV, higher echocardiographic score and higher postprocedural pulmonary artery systolic and left ventricular end-diastolic pressures (p < 0.01).

CONCLUSIONS

Percutaneous balloon mitral commissurotomy has a favorable effect on the hemodynamic variables of mitral stenosis, and long-term follow-up data suggest that it is a viable alternative with respect to surgical commissurotomy in selected patients.

Prevalence and timing of regional myocardial dysfunction after rotational coronary atherectomy

OBJECTIVES

This study aimed to evaluate the prevalence and time course of wall motion abnormalities associated with rotational coronary atherectomy.

BACKGROUND

Although initial clinical studies found evidence of transient wall motion abnormalities after rotational coronary atherectomy, the prevalence and duration of these wall motion abnormalities are unknown.

METHODS

Using simultaneous echocardiography, we prospectively evaluated 22 patients undergoing rotational atherectomy and compared their wall motion abnormalities with those of 10 patients undergoing coronary angioplasty alone. The extent of wall motion abnormality was quantified and plotted against time to produce curves of abnormal wall motion development and recovery for the two groups.

RESULTS

The cumulative ischemic time was similar for the two groups ([mean +/- SD] 10.3 +/- 6 min for rotational atherectomy vs. 9.6 +/- 4.2 min for coronary angioplasty, p = 0.73). The rate of return to baseline function was significantly lower in the rotational atherectomy group than in the coronary angioplasty group (rotational atherectomy rate constant 0.069 +/- 0.079/min vs. coronary angioplasty rate constant 1.250 +/- 0.47/min, p = 0.0001). The mean time to recovery of baseline wall motion in the rotational atherectomy group (153 min, 95% confidence interval [CI] 6.5 to 3,600) was significantly longer than in the coronary angioplasty group (2.6 min, 95% CI 1.3 to 5.5, p = 0.0001). Rotational atherectomy burr time was longer in the patients who developed myocardial infarction than in those without myocardial infarction (4.7 +/- 2.4 vs. 3 +/- 1.4 min, p = 0.045).

CONCLUSIONS

Transient wall motion abnormalities are common after rotational coronary atherectomy and have a longer duration than those observed after coronary angioplasty. This disparity may be a consequence of differences in the mechanisms by which rotational coronary atherectomy and coronary angioplasty produce their effect.

Diagnostic accuracy of antimyosin scintigraphy in suspected myocarditis

BACKGROUND

Radiolabeled antibody specific for cardiac myosin administered intravenously has been used to define noninvasively regions of myocardial necrosis. Inflammatory heart disorders such as myocarditis and heart transplant rejection demonstrate diffuse and often faint myocardial uptake of antimyosin antibody. This study was undertaken to evaluate the reproducibility and diagnostic accuracy of antimyosin antibody imaging for the detection of patients with suspected myocarditis.

METHODS AND RESULTS

Fifty antimyosin scans, performed consecutively in patients with suspected myocarditis, were evaluated by one independent observer and two panels of observers. Antimyosin scan interpretations were compared with endomyocardial biopsy results and also with serial changes in left ventricular function. An independent observer (A) and a panel of five observers (A through E) interpreted the antimyosin scans as positive or negative on the basis of both planar images and tomographic reconstructions. Three of the five observers (A through C) again interpreted the scans but based interpretation only on planar images. Blinded random sequence evaluation of antimyosin scans based on the planar and tomographic interpretations revealed moderate agreement between the independent observer (A) and the group of observers (A through E) (kappa = 0.58). There was also moderate agreement between interpretations based on planar images alone and interpretations based on both planar and tomographic images (kappa [A through E]/[A through C] = 0.57; kappa [A through C]/A = 0.48). Comparison of antimyosin scan results with histologic evidence of myocarditis in endomyocardial biopsy specimens demonstrated that all scan results obtained from the individual or the panels of observers had a very high sensitivity (91% to 100%) and a high negative predictive value (93% to 100%). The specificity (31% to 44%) and positive predictive value (28% to 33%) were less impressive. We also compared the scan and biopsy results with the composite clinical standard of significant left ventricular functional improvement. Endomyocardial biopsy demonstrated poor sensitivity (35%) compared with antimyosin scans (82% to 94%) but had superior specificity (endomyocardial biopsy, 79%; antimyosin scan, 25% to 42%). The specificity of interpretations based on planar and tomographic interpretations (38% to 42%) was better than the planar images alone (25%). If reversible left ventricular dysfunction is considered clinical evidence of myocarditis, this study suggests that a negative endomyocardial biopsy significantly misses the presence of the disease. On the other hand, a negative antimyosin scan almost invariably excludes myocarditis.

CONCLUSIONS

This study demonstrates a high degree of interobserver reproducibility of antimyosin interpretation. Comparison of the scintigraphic results with histologic and clinical standards indicates a high sensitivity of antimyosin scans for the detection of myocarditis. The antimyosin scan is also not likely to miss clinically or pathologically diagnosed myocarditis, in contrast to the endomyocardial biopsy, which missed clinically validated myocarditis 65% of time. The combination of high sensitivity and negative predictive value suggests that antimyosin scintigraphy may be an effective screening procedure for obviating biopsies in patients with suspected myocarditis.

Quantitative assessment of stenotic aortic valve area by using intracardiac echocardiography: in vitro validation and initial in vivo illustration

Quantitative assessment of aortic stenosis (AS) is subject to the limitations of all current noninvasive and invasive methods. The ability to obtain a direct measure of aortic valve area with high resolution by intracardiac echocardiography (ICE) could be of great benefit to catheterized patients. To provide a fixed AS area as an ideal standard for comparison, we performed ICE in 12 sheep hearts with experimentally created AS and five human AS hearts from autopsies. ICE catheters were passed retrograde across the aortic valve, and the minimal orifice area on pullback was planimetered and compared with calibrated video imaging. The entire orifice circumference could be successfully recorded in 16 (94%) hearts. Orifice area from ICE correlated well with actual values (r=0.98; standard error of the estimate [SEE] = 0.06 cm2). To illustrate the applicability in vivo, two canine models and 10 patients with AS were studied. The limiting orifice could be imaged in both animals and in 8 of 10 patients, in whom values agreed well with invasive data (r= 0.95; SEE = 0.04 cm2). ICE can therefore accurately measure AS orifice area in vitro; it can be applied in vivo as well. These validation studies laid the foundation for subsequent clinical studies and applications.

Biopsy-induced flail tricuspid leaflet and tricuspid regurgitation following orthotopic cardiac transplantation

Damage to the tricuspid valve apparatus has been described after endomyocardial biopsy and may be associated with hemodynamically significant tricuspid regurgitation (TR). This study was performed to determine the prevalence of TR and flail tricuspid leaflet in cardiac transplant recipients and to evaluate the use of a 45 cm sheath placed directly in the right ventricle during endomyocardial biopsy to reduce the incidence of these complications. Echocardiograms and right heart catheterization data of 72 orthotopic cardiac transplant recipients were assessed for the presence of flail tricuspid leaflet, TR, and right-sided cardiac dysfunction 29 +/- 20 months (mean +/- SD) after transplantation. Moderate or severe TR was present in 23 patients (32%). Ten patients (14%) had flail tricuspid leaflet, with 7 of these having severe TR. Right atrial pressure (10 +/- 5 vs 6 +/- 5 mm Hg, p < 0.05) was higher, cardiac index (2.0 +/- 0.2 vs 2.5 +/- 0.7 L/min/m2, p < 0.05) was lower, and right-sided cardiac dimensions were greater in patients with flail leaflets than in those without flail leaflets. Both the prevalence of flail tricuspid leaflet (41% to 6%, p < 0.0001) and mean grade of TR (2 to 1, p < 0.0001) were reduced after the use of a 45 cm sheath. We conclude that TR secondary to biopsy-induced damage to the valve apparatus occurs in cardiac transplant recipients and is associated with signs of early right-sided heart failure. Use of a 45 cm sheath during endomyocardial biopsy reduces the prevalence of flail tricuspid leaflet and the severity of TR.