Cardiac imaging of a patient with unusual presentation of granulomatosis with polyangiitis: A case report and review of the literature.

BACKGROUND: Recent evidence suggests that cardiac involvement in patients with granulomatosis with polyangiitis (GPA) occurs more frequently than previously reported. Multimodality cardiac imaging is gaining attention in the diagnosis, prognostication, and follow-up of such patients; however, the data remain scarce. RESULTS: 2D-TTE was useful for initial screening; while both cardiac magnetic resonance imaging and 18F-fluoro-2-deoxyglucose positron emission tomography/computed tomography (18FDG-PET/CT) metabolic imaging with rubidium-82 PET perfusion imaging were useful for characterization of myocardial disease. 18FDG-PET/CT was very useful for the follow-up of cardiac disease activity following treatment. CONCLUSION: 18FDG-PET/CT is sensitive for the detection of cardiac involvement by GPA and is useful for the tissue characterization and follow-up of disease activity following treatment.

Prevalence and Determinants of Hypertension and High Normal Blood Pressure Among Young Adult Saudi Females: Insights Into Preventive Strategies.

This study aimed to determine the prevalence of hypertension and high normal blood pressure and their risk factors among young adult Saudi females. A prospective cross-sectional study was conducted in a women's university. A questionnaire evaluated the subjects' demographic data and risk factors for hypertension and the blood pressure, height, and weight were recorded. In all, 4.1% of the participants were hypertensive and 6.2% had high normal blood pressure. Significant predictors of hypertension/high normal blood pressure were increased body mass index, increased heart rate, walking fewer days per week, and dietary factors. Attention to these risk factors through educational programs is warranted to reduce disease burden in the community.

Awareness among a Saudi Arabian university community of Middle East respiratory syndrome coronavirus following an outbreak.

This study aimed to measure the level of awareness of faculty members, staff and students in a female Saudi Arabian university community towards Middle East respiratory syndrome coronvirus (MERS-CoV) following an outbreak. A self-administered questionnaire containing knowledge questions was distributed and completed by the 1541 participants. The overall knowledge score was 43.2%. It was only significantly higher in participants from the health colleges (50.6%). The majority (78.9%) of the respondents recognized the typical symptoms of MERS-CoV but only 67.1% knew the recommended preventive hygiene practices. Awareness of disease epidemiology, severity, fatality rate and treatment was very low. The knowledge of health care workers/ students of the recommended precautions that should be applied when dealing with patients was poor (55.5%). Significant improvement in educational programmes for both the health care and non-health care professionals is warranted, particularly in crowded educational institutions or workplaces.

Echocardiography in the Assessment of Patients with Rheumatologic Diseases.

Cardiovascular disease is an important extra-articular manifestation of rheumatologic diseases leading to considerable mortality and morbidity. Echocardiography emerges as a useful non-invasive technique for the screening and evaluation of cardiac involvement in these patients. With the technological advancement in echocardiographic techniques, we have gained a greater appreciation of the prevalence and nature of the cardiac involvement in these patients, as detection of subclinical disease is increasingly feasible. This review discusses cardiac involvement in patients with rheumatoid arthritis, systemic lupus erythematosus, anti-phospholipid antibody syndrome, systemic sclerosis and ankylosing spondylitis, and the role of different echocardiographic modalities in their evaluation.

Validation of two-dimensional methods for left atrial volume measurement: a comparison of echocardiography with cardiac computed tomography.

BACKGROUND: Left atrial volume (LAVol) is an important predictor of cardiovascular outcomes. Different formulas are applied to calculate LAVol using two-dimensional transthoracic echocardiography (2DTTE) with variable reference values. The objective of the study was to evaluate the accuracy of methods to calculate LAVol by 2DTTE or cardiac computed tomography (CT). METHODS AND RESULTS: Overall 177 consecutive patients who underwent both a 2DTTE and retrospective electrocardiogram (ECG)-gated coronary CT angiography (CTA) within 15 days were included for this study. LA volume measurements were calculated by 2DTTE and 2DCT using the biplane area-length, biplane Simpson's, prolate-ellipsoid-1 and prolate-ellipsoid-2 methods. These results were compared with those measured by CT using a volumetric method. There was very good correlation between the CT and echocardiographic measures for LAVol, but significant underestimation of the echocardiographic methods when compared to the reference standard (33.5%, 39.1%, 48.1%, and 53.2% for the biplane area-length, biplane Simpson's, prolate-ellipsoid-1, and prolate-ellipsoid-2 methods, respectively). The biplane area-length method using 2DTTE had the closest volume estimation of all echocardiographic methods to the reference standard (67.6 ± 25.5 mL vs. 106 ± 35.5 mL, r = 0.712). Similarly, the biplane area-length method using CT most accurately predicted LAVol (103.3 ± 36.0 mL, r = 0.965). CONCLUSIONS: Compared to CT, 2DTTE provides reasonable assessment of LAVol, although all measurement methods underestimate LAVol. For both 2DTTE and CT, the biplane area-length method appears to provide the most accurate 2D estimate of LAVol.

Tricuspid regurgitation following implantation of a pacemaker/cardioverter-defibrillator.

Tricuspid regurgitation due to permanent pacemaker/defibrillator lead implantation (LITR) has been described more than 3 decades ago, but has come into attention recently due to the dramatic increase in the use of these devices. This entity has not been well defined and its impact on the patient and the health care system is largely unknown. This complication can have important implications. First, the presence and severity of tricuspid regurgitation in general is associated with reduced patient survival, and in the severe cases may require corrective surgery. Second, with the increasing age of the population and the expanding indications of these devices, one expects to encounter many more cases of LITR in the future. Third, this is an iatrogenic complication and therefore potentially preventable. This review discusses the prevalence, mechanisms, and risk factors of LITR as well as the management and potential strategies to prevent its occurrence.

Echocardiographic assessment of primary microvascular angina and primary coronary microvascular dysfunction.

There is an increasing interest in the role of echocardiography in the evaluation of primary microvascular angina, which is attributed to primary coronary microvascular dysfunction. Valid echocardiographic techniques are expected to facilitate the diagnosis and follow-up of these patients and would be valuable for research purposes and therapy evaluation. However, adequate echocardiographic data are lacking, and the interpretation of the limited available literature is hindered by the previous addition of microvascular angina under more inclusive entities, such as cardiac syndrome X. In experienced hands, the assessment of primary coronary microvascular dysfunction in patients with suspected primary microvascular angina, using multiple echocardiographic techniques is feasible, relatively inexpensive, and safe. Exclusion of obstructive epicardial coronary artery disease is, however, a prerequisite for diagnosis. Two-dimensional transthoracic echocardiography, routine stress echocardiography, and speckle-tracking echocardiography indirectly assess primary coronary microvascular dysfunction by evaluating potential impairment in myocardial function and lack diagnostic sensitivity and specificity. Conversely, certain echocardiographic techniques, including Doppler-derived coronary flow velocity reserve and myocardial contrast echocardiography, assess some coronary microvascular dysfunction parameters and have exhibited diagnostic and prognostic potentials. Doppler-derived coronary flow velocity reserve is the best studied and only guideline-approved echocardiographic technique for documenting coronary microvascular dysfunction in patients with suspected microvascular angina. Myocardial contrast echocardiography, by comparison, can detect heterogeneous and patchy myocardial involvement by coronary microvascular dysfunction, which is an advantage over the common practice of coronary flow velocity reserve assessment in a single vessel (commonly the left anterior descending artery) which only reflects regional microvascular function. However, there is no consensus regarding the diagnostic criteria, and expertise performing this technique is limited. Echocardiography remains underexplored and inadequately utilized in the setting of microvascular angina and coronary microvascular dysfunction. Appraisal of the current echocardiographic literature regarding coronary microvascular dysfunction and microvascular angina is important to stay current with the progress in its clinical recognition and create a basis for future research and technological advancements.

Brachial artery occlusion in a young adult with an ACTA2 thoracic aortic aneurysm.

Mutations of the ACTA2 gene, which encodes the smooth muscle cell-specific isoform of α-actin protein, have recently been found to be among the most common genetic abnormalities observed in patients with familial thoracic aortic aneurysms/dissection (TAAD). Other reported vascular manifestations caused by these mutations include premature coronary artery disease and stroke. We report a young adult who presented with an acute brachial artery occlusion and was subsequently found to have aortopathy and an ACTA2 mutation. This expands the spectrum of vascular disease associated with ACTA2 mutation to include acute limb ischemia.

Association of mammographic density and benign breast calcifications individually or combined with hypertension, diabetes, and hypercholesterolemia in women ≥40 years of age: a retrospective study.

Recent evidence has linked certain mammographic characteristics, including breast calcifications (Bcs) and mammographic density (MD), with atherosclerotic cardiovascular disease risk factors in women, but data are limited and inconsistent. We aimed to evaluate the association of MD and/or Bcs with hypertension, diabetes, and hypercholesterolemia in women ≥40 years of age. Through hospital electronic records, we retrospectively identified mammograms of non-pregnant women aged ≥40 years and without breast cancer and retrieved reports and relevant data. MD and Bcs were recorded; risk factor status was diagnosed based on treatment profile and clinical and laboratory data. In total, 1406 women were included. MD was inversely related to hypertension, diabetes, hypercholesterolemia, triglyceride levels, age, and body mass index (BMI) (p value for trend <0.001). Bcs were positively associated with hypertension, diabetes, hypercholesterolemia, age, BMI, and elevated creatinine (p<0.05). Controlling for age and BMI, MD category A (MD-A) was independently associated with hypercholesterolemia; Bcs were independently associated with diabetes. Combining MD-A with Bcs did not increase the odds significantly. Analysis for additive interactions revealed a significant interaction between MD-A and BMI, increasing the odds of hypertension, and a trend for increased odds of diabetes by adding MD-A and/or Bcs to BMI. Decreased MD and presence of Bcs are associated with hypertension, diabetes, and hypercholesterolemia in women ≥40 years of age. MD-A may represent a new obesity index independently associated with hypercholesterolemia and additive to hypertension risk. Bcs are independently associated with diabetes. Combining MD and Bcs did not improve the odds significantly, which may reflect mechanistic differences.

Left atrial-left ventricular angle, a new measure of left atrial and left ventricular remodeling.

We assessed the left atrial-left ventricular (LA-LV) long axis angulation value as a new measure of LA remodeling, and studied its predictors, its effect on two-dimensional LA volume (2D LAVol) estimation, and optimization techniques for 2D LAVol values. Retrospective electrocardiogram-gated coronary computed tomographic angiograms of 164 consecutive patients were reviewed. The LA-LV angle was measured in reconstructed 3-chamber views, and its predictors were determined. The LAVol measured by the area-length method after image optimization along the LV long axis (AL) and the LA long axis (AC-AL), was compared with that measured by the three-dimensional (3D)-volumetric method. LAVol calculation was modified to minimize differences from the 3D values. LA-LV angles ranged from 0° to 63°. In the univariate analysis, decreasing angulation was significantly associated with increasing LV end-diastolic volume (LVEDV), mitral regurgitation grade, LV and LA anteroposterior dimensions, and decreasing LV ejection fraction (LVEF). On multivariate analysis, increasing LVEDV, MR, and LA anteroposterior dimension inversely correlated with angulation; LVEF was positively correlated. The AL and 3D methods significantly differed only for patients with angles ≤ 29.9°. Conversely, LAVol was overestimated for all angules by AC-AL. Modification of AL LAVol using a regression equation, or by substituting the shortest with the longest and average LA lengths in patients with angles ≤ 29.9° and 30-39.9°, respectively neutralized the difference. The LA-LV angle is a new measure of LA and LV remodeling predicted by LV size and function, MR, and LA-anteroposterior dimension. AL formula modifications based on angulation in LV-optimized views better correlate with the 3D method than LA-view modification.

Managing Cardiac Patients: Dentists' Knowledge, Perceptions, and Practices.

OBJECTIVES: Dental patients may require invasive treatment, and awareness of their medical conditions is essential for optimal care. We assessed the knowledge, perceptions, and attitudes of dentists practicing in Saudi Arabia (SA) and their associations with managing patients with common cardiac conditions. METHODS: A national survey of knowledge and attitudes of practicing dentists towards patients with common cardiac conditions was conducted from May 2019 to July 2020 in SA. The survey comprised a newly developed, validated, electronic, self-administered English questionnaire. RESULTS: Overall, 282 dentists completed the survey, of whom 45.5% perceived cardiac patients as difficult to manage, while 64.5% stated that they refer these patients to cardiologists before dental intervention. Regarding knowledge about cardiac conditions, 72% achieved an overall knowledge score <55%; however, their infective endocarditis scores were better. Consultants and specialists (P < .001), those with a PhD/board certification (P = .013), dentists with prior education on cardiac patient management (P = .002), and those working with a cardiologist (P = .016) scored higher on knowledge. Conversely, private dentists (P = .003) and those referring patients to cardiologists before treatment (P = .003) scored lower. Dentists' knowledge of cardiovascular diseases in women was low; only those who believed women experience a greater risk of cardiac complications achieved a higher score. Approximately 90.1% wished to receive education regarding cardiac patient management. CONCLUSIONS: Knowledge of cardiac patient management was suboptimal in this study. Dentists perceived cardiac patients as difficult to manage, but wished to learn more regarding optimal management. Thus, postgraduate education programmes that promote optimal dental management strategies for cardiac patients are necessary.

Vitamin D levels, prediabetes risk and hemoglobin A1c levels in young non-diabetic Saudi women.

AIMS/INTRODUCTION: Vitamin D levels are negatively correlated with prediabetes risk and hemoglobin A1c levels in individuals with prediabetes. The data are, however, scarce and inconsistent among different populations. We aimed to assess the association of vitamin D with prediabetes risk and hemoglobin A1c levels in young Saudi women with normoglycemia and prediabetes. MATERIALS AND METHODS: We analyzed the data of individuals without diabetes (without diabetes history and hemoglobin A1c <6.4%) from the Princess Nourah bint Abdulrahman University's non-communicable diseases student registry. Demographic data, anthropometric and blood pressure measurements, and hemoglobin A1c and vitamin D results were retrieved and analyzed. RESULTS: In total, 345 participants were included in the analysis. The prediabetes status showed no association with vitamin D levels, but it was significantly associated with the participants' weight and body mass index. Additionally, there was no correlation between the levels of vitamin D and hemoglobin A1c across the whole population, even after correction for body mass index. However, in the body mass index subgroups, when individuals with potentially harmful levels of vitamin D (>125 nmol/L) were excluded, a positive association was detected between vitamin D and hemoglobin A1c levels in the underweight individuals. Hemoglobin A1c values showed a positive correlation only with bodyweight and body mass index. CONCLUSIONS: Vitamin D levels did not predict prediabetes status and showed no correlation with hemoglobin A1c levels in this population. Vitamin D levels' effect on the risk of prediabetes might be small compared with other well-established risk factors, such as obesity.

Impact of the 2017 American College of Cardiology/American Heart Association Hypertension Guideline on the prevalence of hypertension in young Saudi women.

BACKGROUND: The diagnostic criteria for hypertension have recently been redefined by the American College of Cardiology/ American Heart Association (ACC/AHA). Data on the new prevalence of hypertension in different countries are emerging, but none, to date, from Saudi Arabia. AIMS: This study aimed to determine the impact of the 2017 ACC/AHA hypertension guideline on the prevalence and determinants of hypertension in young Saudi women. METHODS: 518 female college students, 17-29 years of age were prospectively enrolled in a survey during the period from January 1, 2016, to April 15, 2016 at Princess Nourah University. The participants completed a previously validated questionnaire, that assessed their risk factors for hypertension, and their blood pressure, weight and height were measured. RESULTS: Application of the 2017 ACC/AHA diagnostic criteria resulted in approximately 7-fold increase in the prevalence of hypertension, from 4.1% to 27.1% (P < 0.001). At a cut-off value of ≥140/90, hypertension was significantly associated with increased age, increased body mass index (BMI), increased heart rate, history of chronic illnesses, prior diagnosis with diabetes mellitus and family history of hypertension. Whereas, with the ≥130/80 cut-off value, only increased BMI and heart rate were significant predictors (P < 0.001). CONCLUSION: The prevalence of hypertension markedly increased among young adult Saudi women with the 2017 ACC/AHA classification for hypertension, and the main predictors were increased BMI and heart rate. Further studies on the new prevalence and predictors of hypertension in the Saudi population are warranted. This information is important for healthcare authorities to plan cost effective screening, prevention and control programmes.

Cardiac involvement in disseminated diffuse large B-cell lymphoma, successful management with chemotherapy dose reduction guided by cardiac imaging: A case report and review of literature.

BACKGROUND: Secondary cardiac involvement by lymphoma has received limited attention in the medical literature, despite its grave prognosis. Although chemotherapy improves patients' survival, a subgroup of treated patients dies suddenly due to myocardial rupture following chemotherapy initiation. Reducing the initial chemotherapy dose with dose escalation to standard doses may be effective in minimizing this risk but the data are limited. We report on the successful management of a patient with disseminated diffuse large B-cell lymphoma (DLBCL) involving the heart using such approach. CASE SUMMARY: An 18-year-old male presented to our hospital with six months history of progressive dyspnea, orthopnea and cough. On physical examination, the patient was found to have a plethoric and mildly edematous face, fixed elevation of the right internal jugular vein, suggestive of superior vena cava obstruction, and a pelvic mass. Investigations during admission including a thoracoabdominal computed tomography (CT) scan with CT guided biopsy of the pelvic mass, echocardiography and cardiac magnetic resonance imaging led to the diagnosis of disseminated DLBCL with cardiac involvement. The patients were successfully treated with chemotherapy dose reduction followed by dose escalation to standard doses, under the guidance of cardiac imaging. The patient completed chemotherapy and underwent a successful bone marrow transplant. He is currently in remission and has a normal left ventricular function. CONCLUSION: Imaging-guided chemotherapy dosing may minimize the risk of myocardial rupture in cardiac lymphoma. Data are limited. Management should be individualized.

Primary pulmonary artery sarcoma: A rare and overlooked differential diagnosis of pulmonary embolism. Clues to diagnosis.

INTRODUCTION: Primary pulmonary artery sarcoma (PPAS) is a very rare tumor that mimics pulmonary embolism (PE) in clinical presentation and on imaging studies, therefore leading to diagnostic delay and increased patient mortality. PRESENTATION OF CASE: We discuss the case of 37-year-old man with a rapidly progressing PPAS, which was initially managed as PE. Imaging studies, particularly computed tomography and magnetic resonance imaging, were helpful in reaching the correct diagnosis. Because of the dismal prognosis of such cases, which improves by definite surgery, the patient underwent extensive surgical resection which got complicated by pulmonary reperfusion injury and intrapulmonary hemorrhage, and thus died. DISCUSSION: Owing to the rarity of the tumor, PPAS is often initially mistakenly diagnosed as PE, leading to a diagnostic delay and increased mortality. Having a high index of suspicion in "atypical PE" cases and a knowledge of the characteristic radiological and clinical features of PPAS may expedite the diagnosis and improve survival. Pulmonary artery distension by the mass on imaging studies and compression of neighboring structures are in favor of a tumor rather than PE. Additionally, tissue characterization on magnetic resonance imaging is particularly useful in differentiating tumor from PE. PPAS has a very poor prognosis which improves by early definitive surgery. Perioperative and late mortality however, remain high. CONCLUSIONS: Physicians should be alert of this tumor despite its rarity because diagnostic delay increases mortality. In this report, we summarize the features that differentiate PPAS from PE and the importance of imaging in diagnosing the tumor.

Knowledge and Attitudes Towards Basic Life Support Among Health Students at a Saudi Women's University.

OBJECTIVES: Awareness of basic life support (BLS) is paramount to ensure the provision of essential life-saving medical care in emergency situations. This study aimed to measure knowledge of BLS and attitudes towards BLS training among female health students at a women's university in Saudi Arabia. METHODS: This prospective cross-sectional study took place between January and April 2016 at five health colleges of the Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia. All 2,955 students attending the health colleges were invited to participate in the study. Participants were subsequently asked to complete a validated English-language questionnaire which included 21 items assessing knowledge of BLS and six items gauging attitudes to BLS. RESULTS: A total of 1,349 students completed the questionnaire (response rate: 45.7%). The mean overall knowledge score was very low (32.7 ± 13.9) and 87.9% of the participants had very poor knowledge scores. A total of 32.5% of the participants had never received any BLS training. Students who had previously received BLS training had significantly higher knowledge scores (P <0.001), although their knowledge scores remained poor. Overall, 77.0% indicated a desire to receive additional BLS training and 78.5% supported mandatory BLS training. CONCLUSION: Overall knowledge about BLS among the students was very poor; however, attitudes towards BLS training were positive. These findings call for an improvement in BLS education among Saudi female health students so as to ensure appropriate responses in cardiac arrest or other emergency situations.

Statin-Associated Muscle Adverse Events: Update for clinicians.

Statins are potent medications which reduce low-density lipoprotein cholesterol (LDL-C) levels. Their efficacy in cardiovascular risk reduction is well established and indications for their use are expanding. While statins are generally well tolerated and safe, adverse events are relatively common, particularly statin-associated muscle adverse events (SaMAEs), which are the most frequently encountered type of adverse event. Recent guidelines and guideline updates on SaMAEs and statin intolerance have included revised definitions of SaMAEs, incorporating new evidence on their pathogenesis and management. As SaMAEs emerge as a therapeutic challenge, it is important for physicians to be aware of updates on management strategies to ensure better patient outcomes. The majority of patients who are considered statin-intolerant can nevertheless tolerate some forms of statin therapy and successfully achieve optimal LDL-C levels. This review article discusses the recent classification of SaMAEs with emphasis on pathogenesis and management strategies.

A Plaque Disruption Index Identifies Patients with Non-STE-Type 1 Myocardial Infarction within 24 Hours of Troponin Positivity.

BACKGROUND: Markers of plaque destabilization and disruption may have a role in identifying non-STE- type 1 Myocardial Infarction in patients presenting with troponin elevation. We hypothesized that a plaque disruption index (PDI) derived from multiple biomarkers and measured within 24 hours from the first detectable troponin in patients with acute non-STE- type 1 MI (NSTEMI-A) will confirm the diagnosis and identify these patients with higher specificity when compared to individual markers and coronary angiography. METHODS: We examined 4 biomarkers of plaque destabilization and disruption: myeloperoxidase (MPO), high-sensitivity interleukin-6, myeloid-related protein 8/14 (MRP8/14) and pregnancy-associated plasma protein-A (PAPP-A) in 83 consecutive patients in 4 groups: stable non-obstructive coronary artery disease (CAD), stable obstructive CAD, NSTEMI-A (enrolled within 24 hours of troponin positivity), and NSTEMI-L (Late presentation NSTEMI, enrolled beyond the 24 hour limit). The PDI was calculated and the patients' coronary angiograms were reviewed for evidence of plaque disruption. The diagnostic performance of the PDI and angiography were compared. RESULTS: Compared to other biomarkers, MPO had the highest specificity (83%) for NSTEMI-A diagnosis (P<0.05). The PDI computed from PAPP-A, MRP8/14 and MPO was higher in NSTEMI-A patients compared to the other three groups (p<0.001) and had the highest diagnostic specificity (87%) with 79% sensitivity and 86% accuracy, which were higher compared to those obtained with MPO, but did not reach statistical significance (P>0.05 for all comparisons). The PDI had higher specificity and accuracy for NSTEMI-A diagnosis compared to coronary angiography (P<0.05). CONCLUSIONS: A PDI measured within 24 hour of troponin positivity has potential to identify subjects with acute Non-ST-elevation type 1 MI. Additional evidence using other marker combinations and investigation in a sufficiently large non-selected cohort is warranted to establish the diagnostic accuracy of the PDI and its potential role in differentiating type 1 and type 2 MI in patients presenting with troponin elevation of uncertain etiology.

Allosensitization in heart transplantation: an overview.

Transplant candidates might manifest circulating antibodies against human leukocyte antigens and nonhuman leukocyte antigens, a condition termed allosensitization. The presence of these antibodies decreases a given candidate's possible donor pool, thereby prolonging the time to transplantation. They are also associated with poorer posttransplant outcomes including increased morbidity and mortality. With the increasing use of ventricular assist devices as a bridge to transplantation, the prevalence of allosensitized transplant candidates has increased. This has implications for transplant programs in terms of donor-recipient matching and managing transplant-related complications, which are more common in this high risk cohort. Controversy exists as to the best approach in managing sensitized patients, before and after transplantation. Transplant centres have used various strategies to reduce antibody loads with mixed results being reported; moreover, it remains unclear as to whether attempts at desensitization translate into better posttransplant outcomes. As an alternative management approach, some centres participate in large organ sharing strategies and allocate organs based on the probability of finding a successful donor-recipient match. In this article, the immunological basis of allosensitization, its causes, implications, and therapeutic strategies to manage sensitized patients are reviewed. The literature in relation to desensitization therapies in heart transplant candidates is also reviewed.

Prevalence and mechanism of tricuspid regurgitation following implantation of endocardial leads for pacemaker or cardioverter-defibrillator.

Endocardial lead-induced tricuspid regurgitation has not been well recognized, either clinically or echocardiographically, and yet it is likely a preventable iatrogenic disease. In severe cases, it can lead to right ventricular failure and require tricuspid valve surgery. This complication will become increasingly important, because the numbers of permanent pacemakers and implantable cardioverter-defibrillators are expected to increase because of the aging population and the expanding capabilities of these devices. Published studies are largely retrospective, and serial studies to assess the time course of the development of tricuspid regurgitation are lacking. The mechanisms and severity of tricuspid regurgitation may not be well evaluated by two-dimensional echocardiography. Real-time three-dimensional echocardiography appears to be a promising technique to evaluate the mechanism of tricuspid regurgitation and may allow the early detection of patients who will develop severe lead-induced tricuspid regurgitation. A better understanding of the mechanism of lead-induced tricuspid regurgitation will be essential to the development of preventive strategies, which can then be tested in future clinical trials.