Population-based assessment of familial inheritance and neurologic comorbidities among patients with an isolated atrial septal defect

BACKGROUND

Interatrial shunts, caused by either atrial septal defect (ASD) or patent foramen ovale, have been reported to have a familial association. We sought to examine the familial risk of isolated interatrial shunt and explore associated comorbidities of stroke, transient ischemic attack (TIA), and migraine using a population database.

METHODS

The Utah Population Database is linked to inpatient and outpatient records from the University of Utah Health Science Center. Patients with an interatrial shunt were identified, and those with any other form of congenital heart disease or an inheritable syndrome associated with ASD were excluded. Of the 9452 individuals diagnosed with isolated interatrial shunt, 6179 (65%) had sufficient familial and follow-up data for analysis. Five age/gender matched controls were randomly selected per case. Cases and their relatives were compared with controls to assess the relative risk for each comorbid condition.

RESULTS

Relatives of interatrial shunt cases had an increased risk for interatrial shunt: siblings relative risk (RR) 6.98 (95% confidence interval [CI] 5.75-8.48; P < 1.0 x 10(-16)), first-degree RR 5.64 (95% CI 4.76-6.68; P < 1.0 x 10(-16)), and second-degree RR 1.75 (95% CI 1.32-2.32; P= 0.0001). Patients with interatrial shunt were more likely to have a comorbid condition compared with controls (RR 21.3, 95% CI 17.1-26.5; P < 1.0 x 10(-16)). First-degree relatives of cases had an increased risk of TIA (RR 1.70, 95% CI 1.18-2.45; P= 0.0045), but no increase risk of stroke or migraine compared with controls.

CONCLUSIONS

There is a strong familial inheritance pattern for isolated interatrial shunt, with significantly higher risk of interatrial shunt among affected patients' siblings, first-, and second-degree relatives. Relatives of affected individuals also had a higher risk of TIA, a trend toward an increased risk for stroke, but no increased risk of migraine headache.

Unusual presentation of nickel allergy requiring explantation of an Amplatzer atrial septal occluder device

Systemic allergic reaction to a percutaneous patent foramen ovale (PFO) occlusion device is a rare event with only scattered reports in the literature. Serious allergic reactions to these devices have a poorly defined incidence, presentation, and natural history. We present a woman with a previously unknown nickel allergy who developed severe chest pain beginning the morning after percutaneous device closure of the PFO. Despite multiple visits to her cardiologists and primary care physicians, the cause of her chest pain remained unclear. After seeking a second opinion at our medical center, skin testing showed a severe reaction to nickel. These symptoms were refractory to treatment until device explantation 18 mo later. This case highlights the importance of recognizing nickel allergy as a cause of chest pain following implantation of certain types of devices used for closure of PFOs and other heart defects.

Relationship between accurate auscultation of the fourth heart sound and the level of physician experience

BACKGROUND

Poor performance by physicians-in-training and interobserver variability between physicians has diminished clinicians' confidence in the value of the fourth heart sound (S4).

HYPOTHESIS

We sought to determine if accurate auscultation of an S4 improves with advancing levels of experience.

METHODS

We performed a prospective study of 100 patients undergoing left heart catheterization. Patients underwent blinded auscultation by 4 physicians (each from 1 of 4 different levels of experience), computerized acoustic cardiography, measurement of B-type natriuretic peptide (BNP) levels, echocardiography for measurement of left ventricular ejection fraction (LVEF), and cardiac catheterization for measurement of left ventricular end-diastolic pressure (LVEDP).

RESULTS

While cardiology fellows', residents', and interns' auscultatory findings demonstrated no significant agreement with acoustic cardiography, an S4 auscultated by cardiology attendings had moderate diagnostic accuracy with acoustic cardiography (odds ratio [OR]: 2.31; receiver-operating-characteristic [ROC] area: 0.60). The sensitivities of the S4 were low (39%-46%) for identifying patients with abnormal measures of left ventricular filling pressure (BNP and LVEDP, respectively), and the specificities were fair (76%-80%) with acoustic cardiography. The S4 was not associated with abnormal LVEF. None of the ausculatory groups performed as well as acoustic cardiography in separating patients based on objective measures of left ventricular filling pressure. Acoustic cardiography had the lowest (superior) negative likelihood ratios compared to any ausculatory group.

CONCLUSIONS

The S4 auscultated by cardiology attendings demonstrated superior diagnostic test characteristics compared with internal medicine housestaff and cardiology fellows. Correlations between the S4 and measures of ventricular filling pressure were superior for acoustic cardiography compared to the auscultator groups.

Adjusting for clinical covariates improves the ability of B-type natriuretic peptide to distinguish cardiac from non-cardiac dyspnoea: a sub-study of HEARD-IT

AIMS

We sought to create a model that adjusts B-type natriuretic peptide (BNP) for specific covariates to better distinguish cardiac from non-cardiac dyspnoea.

METHODS AND RESULTS

HEARD-IT was a multicentre, prospective study of the diagnostic utility of acoustic cardiography in the emergency department. Dyspnoeic patients more than 40 years were eligible. Two cardiologists independently adjudicated the HF outcome. Using logistic regression, a model adjusting BNP for pertinent covariates was developed (n = 740). The mean age was 66 +/- 13 years. Age, gender, ethnicity, body mass index, blood urea nitrogen, and creatinine affected BNP levels independently of HF. The model adjusting BNP for these covariates improved the area under receiver operator characteristic curve for HF compared with BNP alone (0.948, 95% CI 0.934-0.963 vs. 0.937, 95% CI 0.920-0.954; P = 0.004). Net reclassification improvement, a novel metric of model performance, was 3.5% for those without HF (P = 0.05) compared with conventional, unadjusted BNP cut-offs. Thirteen of 116 (11%) patients without HF, but with unadjusted BNP values > or =100 pg/mL, were correctly reclassified as not having HF with the adjusted BNP model.

CONCLUSION

Adjusting BNP for important covariates may improve its ability to distinguish cardiac from non-cardiac dyspnoea.

Usefulness of adjusting for clinical covariates to improve the ability of B-type natriuretic peptide to distinguish cardiac from noncardiac dyspnea

Certain clinical characteristics affect brain natriuretic peptide (BNP) levels independently of clinical heart failure (HF). However, it is unclear how to adjust the diagnostic cutoffs of BNP for these variables. We hypothesized that adjusting for important covariates would improve the diagnostic accuracy of BNP for HF in the emergency room setting. We included patients presenting with dyspnea at the Salt Lake City Veterans Affairs Medical Center. Physicians unaware of the BNP values adjudicated the outcome as dyspnea due to HF or noncardiac dyspnea. Subgroup analyses and logistic regression analysis were used to adjust the BNP cutoffs. The mean age of the study population (n = 335) was 72 +/- 11 years. A BNP of 100 pg/ml had a sensitivity of 91%, and a BNP of 400 pg/ml had a specificity of 92%. The covariates age, history of atrial fibrillation, creatinine, and body mass index affected BNP levels independently of HF. The subgroup-specific BNP cutoff that maintained 91% sensitivity was 184 pg/ml for patients > or =75 years, 150 pg/ml for those with atrial fibrillation, and 449 pg/ml for patients with a creatinine > or =2 mg/dl. These subgroup-specific cutoffs improved specificity compared to a cutoff of 100 pg/ml. The regression model that adjusted BNP improved the reclassification of patients as having cardiac or noncardiac dyspnea compared to the conventional BNP cutoffs. Of the patients without HF, 11% were correctly reclassified as having noncardiac dyspnea (p = 0.003). In conclusion, adjusting BNP levels for clinical covariates improves its diagnostic performance.

Acute hemodynamic effects of intravenous nesiritide on left ventricular diastolic function in heart failure patients

BACKGROUND

Nesiritide is recombinant human B-type natriuretic peptide with vasodilatory effects used in patients with decompensated congestive heart failure. We sought to evaluate the effects of nesiritide on left ventricular diastolic function in heart failure patients.

METHODS AND RESULTS

Twenty-five heart failure patients underwent left heart catheterization (using a pressure-volume conductance catheter) and echocardiography at baseline and 30 minutes after an intravenous bolus and infusion of nesiritide. Invasive and noninvasive measurements of load-dependent (deceleration time, echocardiographic diastolic function classification, negative dP/dt, left ventricular diastolic pressure, tau) parameters of diastolic function were assessed. The nonlinear slope of the end-diastolic pressure volume relationship (EDPVR) using 2 single-beat methods for measuring left ventricular end-diastolic elastance was calculated to assess load-independent parameters of diastolic function. Nesiritide reduced biventricular diastolic pressure and systemic vascular resistance. Tau and negative dP/dt showed modest improvement. Deceleration time, isovolumetric relaxation time, diastolic stiffness indices (E/E'/stroke volume (SV) and E/E'/left ventricular end-diastolic volume index (LVEDVI)), and the echocardiographic diastolic filling pattern classification did not change. Furthermore, there was no change in the EDPVR.

CONCLUSIONS

Although nesiritide is an effective vasodilator resulting in decreased left ventricular preload and afterload in heart failure patients, intrinsic left ventricular diastolic function did not change acutely, suggesting that nesiritide has no significant acute lusitropic effect.

Sequence of electrocardiographic and acoustic cardiographic changes and angina during coronary occlusion and reperfusion in patients undergoing percutaneous coronary intervention

BACKGROUND

Previous studies have suggested that ventricular function may be impaired without or prior to electrocardiographic changes or angina during ischemia. Understanding of temporal sequence of electrical and functional ischemic events may improve the detection of myocardial ischemia.

METHODS

A prospective study was performed in 21 subjects undergoing percutaneous coronary intervention (PCI) who had both ST amplitude changes >2 standard deviations above baseline on 12-lead electrocardiography (ECG), and new or increased third or fourth heart sound (S3 or S4) intensity measured by computerized acoustic cardiography. The sequence of the onset and resolution of these signs of ischemia were examined following coronary balloon inflation and deflation.

RESULTS

Electrocardiographic ST amplitude and diastolic heart sound changes occurred contemporaneously, shortly after coronary occlusion (mean onset from balloon inflation; ST changes, 21 +/- 17 seconds; S4, 25 +/- 26 seconds; S3, 45 +/- 43 seconds). In 40% of patients, a new or increased S3 or S4 developed earlier than ST changes. Anginal symptoms occurred in only 2 of the 21 subjects during ischemia with a mean onset time of 68 seconds. ST-segment changes resolved earliest (33 seconds after balloon deflation) while diastolic heart sounds (89 +/- 146 seconds) and angina (586 +/- 653 seconds) resolved later.

CONCLUSION

A new or intensified S3 and/or S4 occurred contemporaneously with electrocardiographic changes during ischemia. These diastolic heart sounds persisted longer than ST changes following coronary reperfusion. Acoustic cardiographic assessment of diastolic heart sounds may aid in the early detection of myocardial ischemia, particularly in those patients with an uninterpretable ECG.

Hemodynamic correlates of the third heart sound and systolic time intervals

Bedside diagnostic tools remain important in the care of patients with heart failure. Over the past two centuries, cardiac auscultation and phonocardiography have been essential in understanding cardiac pathophysiology and caring for patients with heart disease. Diastolic heart sounds (S3 and S4) and systolic time intervals have been particularly useful in this regard. Unfortunately, auscultation skills have declined considerably, and systolic time intervals have traditionally required carotid pulse tracings. Newer technology allows the automated detection of heart sounds and measurement of systolic time intervals in a simple, inexpensive, noninvasive system. Using the newer system, the authors present data on the hemodynamic correlates of the S3 and abnormal systolic time intervals. These data serve as the foundation for using the system to better understand the test characteristics and pathophysiology of the S3 and systolic time intervals, and help to define their use in improving the bedside diagnosis and management of patients with heart failure.

Does higher diastolic augmentation predict clinical benefit from enhanced external counterpulsation?: Data from the International EECP Patient Registry (IEPR)

BACKGROUND

Enhanced external counterpulsation (EECP) has been demonstrated to be an effective treatment for stable angina in patients with coronary disease. The hemodynamic effects of EECP are maximized when the ratio of diastolic to systolic pressure area is in the range of 1.5 to 2.0.

HYPOTHESIS

It is hypothesized that patients undergoing EECP who are able to achieve higher diastolic augmentation (DA) ratios may derive greater clinical benefit. This study examines the relationship between the DA ratio and clinical outcomes in patients undergoing EECP.

METHODS

We analyzed demographic, noninvasive hemodynamic, and clinical outcome data on 1,004 patients enrolled in the International EECP Patient Registry (IEPR) for treatment of chronic angina between January 1998 and August 1999. Blood pressure waveforms were recorded from finger plethysmography. Six-month clinical outcomes were obtained by telephone interview.

RESULTS

At the end of EECP treatment, 370 (37%) patients had a higher DA ratio (defined as > or = 1.5) and 634 (63%) had a lower DA ratio (defined as < 1.5). Factors associated with a lower DA ratio included age > or =65 years (p <0.001), female gender (p < 0.001), left ventricular ejection fraction < 35% (p < 0.05), hypertension (p < 0.01), prior coronary bypass surgery (p < 0.01), noncardiac vascular disease (p < 0.001), multivessel disease (p < 0.01), congestive heart failure (p < 0.01), current smoking (p < 0.01), unsuitability for further revascularization (p < 0.001), and higher baseline angina class (p < 0.001). There were no significant differences regarding diabetes mellitus, prior coronary angioplasty, prior myocardial infarction, or antianginal medication use between patients with higher or lower DA ratios. Based on a multiple logistic regression model, independent predictors of a DA ratio < 1.5 at the end of EECP included current smoking (odds ratio 3.3; 95% confidence intervals 2.0-5.4); multivessel disease (1.7; 1.3-2.3); female gender (2.2; 1.7-3.0); no prior EECP (1.9; 1.1-3.3); noncardiac vascular disease (2.3; 1.7-2.9); age > or = 65 years (1.7; 1.4-2.2), and patients not suitable for revascularization (1.6; 1.2-2.0). By the end of therapy, there were no significant differences in myocardial infarction, revascularization rates, or nitroglycerin use with respect to higher DA ratios. At 6-month follow-up, patients with higher DA had a trend toward a greater reduction in angina class compared with those with lower DA (p = 0.069). There was a significantly higher rate of unstable angina and congestive heart failure in the group not achieving higher augmentation (p < 0.05).

CONCLUSIONS

Patients who are younger, male, nonsmoking, and without multivessel coronary or noncardiac vascular disease are most likely to have higher DA with EECP. Patients with higher DA tended to have a greater reduction in angina class at 6-month follow-up compared with those with lower DA ratios. There is evidence that higher DA ratios are associated with improved short- or long-term clinical outcomes, suggesting that clinical benefit from EECP is associated with the magnitude of DA.

Multivessel coronary thrombosis treated with abciximab (ReoPro) in a patient with essential thrombocythemia

A 50-year-old man was admitted with acute inferior and anterior myocardial infarction. The patient was diagnosed with essential thrombocythemia (ET) based on the findings of marked thrombocytosis of 1,113 x 10(3)/mm3, splenomegaly, and numerous clumping megakaryocytes on bone marrow biopsy. Emergent coronary angiography revealed extensive multivessel thrombosis involving the left main coronary artery and completely occluding the proximal right coronary artery. In addition to standard therapy with aspirin, heparin, and primary angioplasty of the right coronary artery, the patient received additional antiplatelet therapy with ticlopidine, hydroxyurea, and the platelet glycoprotein IIb/IIIa receptor-inhibiting monoclonal antibody drug abciximab (ReoPro). Serial coronary angiograms 1 and 5 days following the infarction showed progressive thrombus resolution. The pathophysiologic mechanisms and therapeutic challenges of ET-associated coronary thrombosis are discussed in this report.

Passive tobacco exposure may impair symptomatic improvement in patients with chronic angina undergoing enhanced external counterpulsation

Background

The adverse effects of tobacco abuse on cardiovascular outcomes are well-known. However, the impact of passive smoke exposure on angina status and therapeutic response is less well-established. We examined the impact of second-hand smoke (SHS) exposure on symptomatic improvement in patients with chronic ischemic coronary disease undergoing enhanced external counterpulsation (EECP).

Methods

This observational study included 1,026 non-smokers (108 exposed and 918 not-exposed to SHS) from the Second International EECP Patient Registry. We also assessed angina response in 363 current smokers. Patient demographics, symptomatic improvement and quality of life assessment were determined by self-report prior and after EECP treatment.

Results

Non-smoking SHS subjects had a lower prevalence of prior revascularization (85% vs 90%), and had an increased prevalence of stroke (13% vs 7%) and prior smoking (72% vs 61%; all p < 0.05) compared to non-smokers without SHS exposure. Despite comparable degrees of coronary disease, baseline angina class, medical regimens and side effects during EECP, fewer SHS non-smokers completed a full 35-hour treatment course (77% vs 85%, p = 0.020) compared to non-smokers without SHS. Compared to non-smokers without SHS, non-smoking SHS subjects had less angina relief after EECP (angina class decreased ≥ 1 class: 68% vs 79%; p = 0.0082), both higher than that achieved in current smokers (66%). By multivariable logistic regression, SHS exposure was an independent predictor of failure to symptomatic improvement after EECP among non-smokers (OR 1.81, 95% confidence intervals 1.16–2.83).

Conclusion

Non-smokers with SHS exposure had an attenuated improvement in anginal symptoms compared to those without SHS following EECP.