Nocturia and Blood Pressure Elevation in Adolescents.

Nocturia has been increasingly recognized as a manifestation of various non-urological conditions including hypertension. In adults, blood pressure (BP) elevation has been identified as a robust correlate of nocturia, but such a relationship has not been studied in pediatric populations where nocturia is often attributed to hormonal, sleep, physiological or psychological disorders. Accordingly, this study aimed to determine the relationship between nocturia and BP elevation in adolescents. We prospectively studied 100 patients, aged 10-18 years, recruited from pediatric clinics at our institution. Nocturia (defined as ≥ 1 voids on voiding diary analysis) was present in 45% of the study sample (range: 1-4 voids/night). 37% of subjects self-reported awakening to urinate, and 34% of subjects had BP elevation according to age-dependent thresholds from current Pediatrics guidelines. On multivariate analyses, BP elevation was strongly associated with nocturia determined by both voiding diary (OR 26.2, 95% CI: 6.5, 106.0) and self-report. Conversely, nocturia was associated with increased odds of elevated BP by diary (26.3, 95% CI: 6.5, 106.4) and self-report (OR 8.1, 95% CI: 3.2, 20.5). In conclusion, nocturia appears to be common and is strongly associated with BP elevation in adolescents. These findings suggest that eliciting a history of nocturia holds promise as a simple method of identifying adolescents at risk for hypertension.

Home Blood Pressure Monitoring And Nocturia In Adults.

Although widely viewed as a urological condition, nocturia has been increasingly recognized to accompany various non-urological conditions such as hypertension and blood pressure (BP) elevation on office determination. Home BP monitoring (HBPM) has been shown superior to office-based readings and provides an opportunity to assess potential relationships between nocturia and novel indices derived from multiple BP recordings including BP load, BP variability, and arterial stiffness, which have prognostic significance. We retrospectively studied 103 home BP logs and nocturia frequencies provided by 61 stable cardiology patients ≥ 21 years without medication change. Nocturnal voids ranged from 0 to 5 voids per night, median: 1.5. Nocturia frequency was significantly correlated with home and office systolic BPs and with BP load, but not with diastolic BPs, BP variability or arterial stiffness. On Poisson regression analysis, the estimated prevalence ratio (PR) for home and office systolic BPs were 1.025 (CI: 1.01, 1.04; p < .001) and 1.01 (CI:1.00, 1.02; p = .019), indicating 2.5% and 1% increases in the risk of nocturia per mmHg increases in BP respectively. In conclusion, higher mean home and office systolic BPs are associated with self-reported nocturia frequency with stronger associations seen for home BP measurement. Nocturia frequency appears unrelated to mean home and office diastolic BPs. Nocturia may be related to BP load, (percentage of elevated BP values), but not to BP variability or arterial stiffness. Future prospective studies using HBPM are needed to confirm these findings and to contribute to the understanding of the elevated BP-nocturia link.

Assessment of Cardiovascular Disease Among Predominantly Black Gout Patients.

INTRODUCTION: Although the association between gout and cardiovascular disease (CVD) has been extensively studied, scarce data are available for the Black population. We aimed to assess the association between gout and CVD in a predominantly Black urban population with gout. METHODS: A cross-sectional analysis was performed between a gout cohort and an age-/sex-matched control group. Clinical parameters and 2D echocardiograms were reviewed for the patients with gout and heart failure (HF). The primary outcome studied includes the prevalence and strength of association between gout and CVD. Secondary outcomes studied includes strength of association of gout and HF categorized by ejection fraction, mortality, and HF readmissions. RESULTS: Four hundred seventy-one patients with gout had a mean age of 63.7 ± 0.5 years; 89% were Black, 63% were men, and mean body mass index was 31.3 ± 0.4 kg/m 2 . Hypertension, diabetes mellitus, and dyslipidemia were present in 89%, 46%, and 52%, respectively. Compared with controls, patients with gout had significantly higher rates of angina, arrhythmia, coronary artery disease/stents, myocardial infarction, coronary artery bypass graft surgery, cerebrovascular accident, and peripheral vascular disease. The adjusted odds ratio for CVD was 2.9 (95% confidence interval, 1.9-4.5; p < 0.001). Gout patients had a higher prevalence of HF with 45% (n = 212) compared with controls with 9.4% (n = 44). Adjusted odds ratio for HF risk was 7.1 (95% confidence interval, 4.7-10.6; p < 0.01). CONCLUSIONS: Gout in a predominantly Black population confers 3 times the CVD risk and 7 times HF-specific risk compared with age- and sex-matched cohort. Further research is needed to confirm our findings and to develop interventions to reduce morbidity associated with gout.

Sleep Apnea as a Risk Factor for Diastolic Dysfunction: A Systematic Review and Meta-Analysis.

BACKGROUND: This meta-analysis assessed the relationship between obstructive sleep apnea (OSA) and echocardiographic parameters of diastolic dysfunction (DD), which are used in the assessment of heart failure with preserved ejection fraction. METHODS: We searched the databases including Ovid MEDLINE, Ovid Embase, Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 26, 2020. The search was not restricted to time, publication status, or language. Two independent investigators screened the identified studies and extracted the data in duplicate. We conducted a meta-analysis using RevMan v.5. The risk of bias was assessed using Cochrane collaboration tools. Comparisons were made between patients with OSA, diagnosed in-laboratory polysomnography or home sleep apnea testing, and patients without OSA in relation to established markers of DD. RESULTS: Primary search identified 2,512 studies. A total of 18 studies including 2,509 participants were included. The two groups were free of conventional cardiovascular risk factors. Significant structural changes were observed between the two groups. Patients with OSA exhibited greater left atrial volume index (LAVI) (3.94 95% CI [0.8, 7.07]; p = 0.000) and left ventricular mass index (11.10 95% CI [2.56, 19.65]; p = 0.000) as compared to control group. The presence of OSA was also associated with more prolonged deceleration time (10.44 ms 95% CI [0.71, 20.16]; p = 0.04), isovolumic relaxation time (IVRT) (7.85 ms 95% CI [4.48, 11.22]; p = 0.000), and a lower ratio of early to late mitral inflow velocities (E/A) ratio (-0.62 95% CI [-1, -0.24]; p = 0.001) suggestive of early DD. The early mitral inflow velocity to mitral annular early diastolic velocity (E/e') ratio (0.94 95% CI [0.44, 1.45]; p = 0.000) was increased. Linear correlation between severity of OSA and LAVI and IVRT parameters was observed but this association did not sustain for the E/A and E/e'. The ejection fraction was not significantly different between patients with OSA and healthy controls (-0.48 95% CI [-1.18, 0.23]; p = 0.18). CONCLUSION: An association between OSA and echocardiographic parameters of DD was detected that was independent of conventional cardiovascular risk factors. OSA may be independently associated with DD perhaps due to higher LV mass. Investigating the role of continuous positive airway pressure therapy in reversing or ameliorating DD is recommended.

Treatment of Sleep Apnea with Positive Airway Pressure and Its Association with Diastolic Dysfunction: A Systematic Review and Meta-Analysis.

BACKGROUND: This meta-analysis assessed the effect of long-term (>6 weeks) noninvasive positive airway pressure (PAP) on diastolic function in patients with obstructive sleep apnea (OSA). METHODS: We searched the databases for randomized clinical trials including Ovid MEDLINE, Ovid Embase Scopus, Web of Science, Google Scholar, and EBSCO CINAHL from inception up to December 20, 2019. The search was not restricted to time, publication status, or language. Two independent investigators screened the studies and extracted the data, in duplicate. Risk of bias was assessed using Cochrane collaboration tools. RESULTS: A total of 2,753 abstracts were resulted from literature search. A total of 9 randomized clinical trials assessing the effect of long-term (>6 weeks) PAP on diastolic function in patients with OSA including 833 participants were included. The following echo parameters were found in treated patients: a decrease in deceleration time (-39.49 ms CI [-57.24, -21.74]; p = 0.000), isovolumic relaxation time (-9.32 ms CI [-17.08, -1.57]; p = 0.02), and the ratio of early mitral inflow velocity to mitral annular early diastolic velocity (-1.38 CI [-2.6, -0.16]; p = 0.03). However, changes in left-atrial volume index and the ratio of early to late mitral inflow velocities were not statistically different. The risk of bias was mild to moderate among the studies. CONCLUSION: Our results suggest that chronic treatment of moderate to severe OSA with noninvasive PAP is associated with improvement in echocardiographic findings of diastolic dysfunction.

Characterization of microvascular disease in pediatric sickle cell disease using nailfold capillaroscopy.

Sickle cell disease (SCD) is a disorder with repetitive vaso-occlusive crises resulting in microvascular obstruction and tissue ischemia that may lead to multi-organ ischemia and dysfunction. Nailfold videocapillaroscopy (NFC) is an imaging technique utilized in clinical rheumatology to visualize capillaries located near the fingertip. To characterize NFC abnormalities in the setting of pediatric SCD, we performed NFC using a video capillaroscope on 8 digits in 44 stable SCD patients and 65 age matched healthy controls. Mean capillary number was lower (6.4 ± 1.3 vs 7.5 ± 1.8, p = 0.001) in the SCD group compared to controls. The percentage of dilated capillaries was similar (7.1 ± 8.3 vs. 5.9 ± 8.2, p = 0.4). The large majority of capillaries visualized in the SCD and control groups were normal capillary types per the EULAR definition, with a similar percentage of normal, nonspecific capillary morphologies and abnormal types. Regarding normal capillary sub-types, the SCD group and controls exhibited similar percentages of stereotype hairpin shapes, and tortuous or once or twice crossing type capillaries. On multivariate analyses, mean capillary number was independently associated with SCD after adjusting for age, body mass index, systolic blood pressure and gender. In conclusion, pediatric SCD is associated with lower capillary number but similar percentage of dilated capillaries and morphology on NFC. In our SCD cohort, capillary number was unrelated to our available markers of disease severity, including history of sickle crises, previous hospitalization for crises or Hemoglobin F levels.

Characterization of microvascular disease in patients with sickle cell disease using nailfold capillaroscopy.

Sickle cell disease (SCD) is a disorder characterized by repetitive vaso-occlusive crises causing microvascular obstruction, tissue ischemia and pain that may lead to chronic multi-organ ischemic sequelae. Nailfold videocapillaroscopy (NFC) is a non-invasive imaging technique used in clinical rheumatology to directly visualize capillaries located near the fingertip. To characterize NFC abnormalities in the setting of SCD, we performed NFC on 71 SCD patients and 70 age matched controls using a video capillaroscope on 8 digits. As compared to controls, mean capillary number was lower and the final capillary score (measure of capillary dropout inversely related to capillary density) was higher in the SCD group. The SCD group had a lower percentage of stereotype hairpin shapes and a higher percentage of crossing type capillaries. On multivariate linear analyses, both mean capillary number and final capillary score were independently associated with SCD after adjusting for age, body mass index, and gender. SCD was associated with more dilated capillaries but similar numbers of hemorrhages. In conclusion, SCD is associated with lower capillary density and more dilated capillaries on NFC. These changes appear unrelated to markers of disease severity including frequency of sickle crises, number of transfusions, and HbS levels. The relation between NFC and target organ involvement merits further study.

Relation of the Ankle Brachial Index to Left Ventricular Ejection Fraction in Patients Without Coronary Artery Disease.

BACKGROUND: The low ankle brachial index (ABI) values are indicative of peripheral arterial disease, but have recently been found to be associated with reduced left ventricular ejection fraction (LVEF). This may relate to coexisting coronary artery disease (CAD). AIM: This study prospectively assessed a potential ABI-LVEF association in patients without CAD. METHODS AND RESULTS: We studied 55 patients (age 57 ± 13 years, 49% male) with normal coronary arteries with LVEF determination. ABI, pulse wave velocity (PWV), and augmentation index (AI) were performed after coronary angiography. ABI correlated with LVEF (r = 0.40, p = 0.002), but not with PWV or AI. On linear regression analysis, ABI was independently associated with LVEF (B = 0.42, p = 0.004). The median LVEF was lower in subjects with low ABI values compared to those with normal ABI values (33 vs. 61%; p = 0.001). CONCLUSION: ABI may be influenced by LVEF independently of CAD, arterial stiffness or pressure wave reflection.

Discontinuation/Dose Reduction of Angiotensin-Converting Enzyme Inhibitors/Angiotensin Receptor Blockers during Acute Decompensated Heart Failure in African-American Patients with Reduced Left-Ventricular Ejection Fraction.

OBJECTIVES: Patients with heart failure (HF) and reduced left-ventricular ejection fraction (LVEF) benefit from angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blocker (ARB) therapy. While dose reduction/discontinuation (r/d) of ß-blockers (BB) and furosemide in acute decompensated HF (ADHF) worsen outcomes, data on ACEI/ARB are lacking. METHODS: To determine the frequency and reasons for ACEI/ARB therapy r/d in ADHF patients, we studied 174 patients with LVEF <40% on ACEI/ARB and BB therapy upon admission over 1 year. RESULTS: ACEI/ARB doses were r/d in 17.2% because of acute kidney injury (56.7%), hypotension (23.3%), and hyperkalemia (10%). Clinical characteristics were similar between patients with r/d and continued therapy. Admission and discharge creatinine (Cr) levels were higher in the r/d group. On multivariate analysis, admission Cr and admission systolic blood pressures were independent predictors of r/d. Among patients with renal dysfunction cited as the r/d reason, Cr did not significantly rise in 23.5%. The r/d group had a longer length of stay (LOS). CONCLUSIONS: ACEI/ARB dose is reduced and/or discontinued in nearly one-fifth of all ADHF admissions, and LOS is longer in the ACEI/ARB r/d group. While impaired renal function is the most frequently cited reason, nearly one-fourth of the patients had stable renal function. ACEI/ARB r/d therapy in the setting of ADHF merits further study.

Effects of Ischemic Reperfusion Injury and Remote Conditioning on Passive Leg Raising-Induced Brachial-Artery Dilation.

OBJECTIVES: Passive leg raising (PLR) has been proposed to assess arterial vasodilator reserve and possibly endothelial function. Since endothelial function is sensitive to ischemic-reperfusion (I-R) injury, we determined the effects of I-R injury and ischemic conditioning on PLR-induced brachial-artery dilation (BAD), i.e. PLR-BAD. METHODS: We induced PLR-BAD before and after ipsilateral arm I-R injury (7.5 min of occlusion) in 20 healthy males aged 29 ± 6 years. The protocol was repeated in combination with remote conditioning stimuli (3 × 30 s of contralateral arm occlusions). RESULTS: PLR resulted in significant BAD (3.85%, p < 0.001) before but not after prolonged ischemia (0.25%, p = 0.38). I-R injury, along with either preischemic or postischemic conditioning restored the PLR-BAD response (before: 3.11%, p < 0.001 and after: 3.74%, p < 0.001). CONCLUSIONS: I-R injury blunts the BAD induced by PLR. Remote pre- and postconditioning restore this response. These findings are similar to those previously reported using hyperemia and ultrasound to assess BAD.

The ankle-brachial index is related to left ventricular ejection fraction in bonnet macaques.

UNLABELLED: Low ankle-brachial index (ABI) is a marker of peripheral arterial disease associated with higher cardiovascular risk. ABI has been found to be influenced by left ventricular ejection fraction (LVEF), but this relation is confounded by atherosclerosis. OBJECTIVES: Since nonhuman primates have a low incidence of atherosclerosis, we sought to evaluate the effect of LVEF on ABI in 24 healthy female bonnet macaques (age 83 ± 21 months). METHODS: LVEF was determined by echocardiography during anesthesia with ketamine. ABI was determined using automatic blood pressure cuff. RESULTS: Mean LVEF was 73 ± 6%. Mean ABI was 1.03 (range 0.78-1.17) with similar right and left lower limb values (p = 0.78). On univariate analysis, mean ABI was significantly correlated with LVEF (r = 0.58, p = 0.003) but not with age, crown-rump length or weight. Mean LVEF increased in a stepwise manner from lowest to highest ABI tertile (68 ± 6 vs. 73 ± 4 vs. 77 ± 5%, p = 0.008). On ordinal regression and forced multivariate linear analyses, ABI status was independently related to LVEF. CONCLUSIONS: ABI is influenced by left ventricular systolic function but not age, height, weight or mass index in bonnet macaques. Left ventricular systolic function should be accounted for when considering ABI measurements.

Idiopathic Ventricular Tachycardia in the Presence of Triple-Vessel Coronary Artery Disease: A Case Report.

Exercise-induced ventricular tachycardia undergoes ischemia evaluation; however, it is important to identify idiopathic ventricular tachycardia in patients with concomitant coronary artery disease and radiofrequency ablations can be lifesaving. We report a case of exercise-induced right and left ventricular outflow tract ventricular tachycardia in a patient with triple vessel coronary artery disease.

Cardiac lineage protein-1 (CLP-1) regulates cardiac remodeling via transcriptional modulation of diverse hypertrophic and fibrotic responses and angiotensin II-transforming growth factor ß (TGF-ß1) signaling axis.

It is well known that the renin-angiotensin system contributes to left ventricular hypertrophy and fibrosis, a major determinant of myocardial stiffness. TGF-ß1 and renin-angiotensin system signaling alters the fibroblast phenotype by promoting its differentiation into morphologically distinct pathological myofibroblasts, which potentiates collagen synthesis and fibrosis and causes enhanced extracellular matrix deposition. However, the atrial natriuretic peptide, which is induced during left ventricular hypertrophy, plays an anti-fibrogenic and anti-hypertrophic role by blocking, among others, the TGF-ß-induced nuclear localization of Smads. It is not clear how the hypertrophic and fibrotic responses are transcriptionally regulated. CLP-1, the mouse homolog of human hexamethylene bis-acetamide inducible-1 (HEXIM-1), regulates the pTEFb activity via direct association with pTEFb causing inhibition of the Cdk9-mediated serine 2 phosphorylation in the carboxyl-terminal domain of RNA polymerase II. It was recently reported that the serine kinase activity of Cdk9 not only targets RNA polymerase II but also the conserved serine residues of the polylinker region in Smad3, suggesting that CLP-1-mediated changes in pTEFb activity may trigger Cdk9-dependent Smad3 signaling that can modulate collagen expression and fibrosis. In this study, we evaluated the role of CLP-1 in vivo in induction of left ventricular hypertrophy in angiotensinogen-overexpressing transgenic mice harboring CLP-1 heterozygosity. We observed that introduction of CLP-1 haplodeficiency in the transgenic α-myosin heavy chain-angiotensinogen mice causes prominent changes in hypertrophic and fibrotic responses accompanied by augmentation of Smad3/Stat3 signaling. Together, our findings underscore the critical role of CLP-1 in remodeling of the genetic response during hypertrophy and fibrosis.

Left ventricular systolic function in sickle cell anemia: a meta-analysis.

BACKGROUND: We sought to evaluate whether patients with sickle cell anemia (SCA) have left ventricular (LV) systolic dysfunction. METHODS AND RESULTS: We conducted a Medline, Embase, Ebscohost, and Google scholar literature search articles published before April 2010. All studies that compared any measure of LV function (eg, ejection fraction [EF], fractional shortening [FS], or cardiac index [CI]) between normal control subjects and SCA (hemoglobin SS) patients were included. Among 57 studies that qualified for review, 19 studies including 841 SCA patients and 554 control subjects met the inclusion criteria. There were no significant differences in either LVEF (Hedge g = 0.15; 95% confidence interval -0.84 to 1.14; P = .76) or FS (P = .28) between SCA patients and control subjects. CI was significantly higher (P < .001) and LV end-systolic stress-volume index (load independent) was significantly lower (P < .001) in SCA patients. All LV systolic measures inversely correlated with age (all P < .001). LV end-systolic and -diastolic dimensions were significantly higher in SCA patients and increased with age. CONCLUSIONS: SCA patients have similar load-dependent but lower load-independent measures of LV systolic function than control subjects. SCA is associated with LV dilation. LV structural and functional abnormalities appear to be age dependent with progressive LV dilation and impairment over time.

Comparison of passive leg raising and hyperemia on macrovascular and microvascular responses.

Passive leg raising is a simple diagnostic maneuver that has been proposed as a measure of arterial vasodilator reserve and possibly endothelial function. While passive leg raising has previously been shown to lower blood pressure, increase flow velocity and cause brachial artery dilation, its effects on microvascular flow has not been well studied. Also, passive leg raising has been directly compared previously to upper arm but never to lower arm occlusion of blood flow induced hyperemia responses. We compared changes in macrovascular indices measured by brachial artery ultrasound and microvascular perfusion measured by Laser Doppler Flowmetry induced by passive leg raising to those provoked by upper arm and lower arm induced hyperemia in healthy subjects. Upper arm induced hyperemia increased mean flow velocity by 398%, induced brachial artery dilatation by 16.3%, and increased microvascular perfusion by 246% (p<.05 for all). Lower arm induced hyperemia increased flow velocity by 227%, induced brachial artery dilatation by 10.8%, and increased microvascular perfusion by 281%. Passive leg raising increased flow velocity by 29% and brachial artery dilatation by 5.6% (p<.05 for all), but did not change microvascular perfusion (-5%, p=ns). In conclusion, passive leg raising increases flow velocity orders of magnitude less than does upper arm or lower arm induced hyperemia. Passive leg raising-induced brachial artery dilatation is less robust than either of these hyperemic techniques. Finally, although upper arm and lower arm hyperemia elicits macrovascular and microvascular responses, passive leg raising elicits only macrovascular responses.

Determination of heart rate variability with an electronic stethoscope.

INTRODUCTION: Heart rate variability (HRV) is widely used to characterize cardiac autonomic function by measuring beat-to-beat alterations in heart rate. Decreased HRV has been found predictive of worse cardiovascular (CV) outcomes. HRV is determined from time intervals between QRS complexes recorded by electrocardiography (ECG) for several minutes to 24 h. Although cardiac auscultation with a stethoscope is performed routinely on patients, the human ear cannot detect heart sound time intervals. The electronic stethoscope digitally processes heart sounds, from which cardiac time intervals can be obtained. METHODS: Accordingly, the objective of this study was to determine the feasibility of obtaining HRV from electronically recorded heart sounds. We prospectively studied 50 subjects with and without CV risk factors/disease and simultaneously recorded single lead ECG and heart sounds for 2 min. RESULTS: Time and frequency measures of HRV were calculated from R-R and S1-S1 intervals and were compared using intra-class correlation coefficients (ICC). CONCLUSION: The majority of the indices were strongly correlated (ICC 0.73-1.0), while the remaining indices were moderately correlated (ICC 0.56-0.63). In conclusion, we found HRV measures determined from S1-S1 are in agreement with those determined by single lead ECG, and we demonstrate and discuss differences in the measures in detail. In addition to characterizing cardiac murmurs and time intervals, the electronic stethoscope holds promise as a convenient low-cost tool to determine HRV in the hospital and outpatient settings as a practical extension of the physical examination.

A Rare Case of Coexisting Mutation in Desmin and Thioredoxin Reductase 2 Genes Causing Dilated Cardiomyopathy.

Desmin (DES) maintains the overall structure of cardiomyocytes and cytoskeletal organization within striated muscle cells. Mitochondrial thioredoxin reductase 2 (TXNRD-2) is essential for mitochondrial oxygen radical scavenging. We describe a rare case of dilated cardiomyopathy (DCM) in an 18-year-old female with a heterozygous mutation involving both DES and TXNRD-2 genes.

The role of complement C3 in the outcome of regional myocardial infarction.

Coronary heart disease leading to myocardial ischemia is a major cause of heart failure. A hallmark of heart failure is myocardial fibrosis. Using a murine model of myocardial ischemia/reperfusion injury (IRI), we showed that, following IRI, in mice genetically deficient in the central factor of complement system, C3, myocardial necrosis was reduced compared with WT mice. Four weeks after the ischemic period, the C3-/- mice had significantly less cardiac fibrosis and better cardiac function than the WT controls. Overall, our results suggest that innate immune response through complement C3 plays an important role in necrotic cell death, which contributes to the cardiac fibrosis that underlies post-infarction heart failure.

Transthyretin Cardiac Amyloidosis Presenting as Bradycardia, Renal Failure, Atrioventricular-Nodal Blockade, Shock, and Hyperkalemia (BRASH) Syndrome: A Case Report.

BRASH syndrome involves the chain of events resulting from the collective effects of Bradycardia, Renal failure, Atrioventricular (AV)-nodal blockade, Shock, and Hyperkalemia. BRASH syndrome can rapidly progress to cardiac arrest. Early recognition is crucial. We present a case of transthyretin cardiac amyloidosis (ATTR-CA) in an elderly woman who presented with BRASH syndrome shortly after an AV-nodal blocker was prescribed for atrial fibrillation.

Prion protein as a mediator of neurocardiosympathetic interactions.

A proteomic approach to study cardiovascular disease includes the examination of proteins associated with risk factors such as left ventricular hypertrophy (LVH). PrP(C) is a host-coded membrane-bound glycoprotein found in most cell types, including myocardium, and whose physiological function is uncertain. We have taken a selective proteomic approach and performed mechanistic studies to determine whether PrP(C) levels are related to left ventricular (LV) structure or function. Echocardiograms were performed at baseline in 65 mice comprising three strains of the same C57Bl/6J × 129SV genetic background but expressing different levels of PrP(C) (wild-type mice (WT), PrP(-/-) , and PrP(C) over-expressing transgenic mice (tga20)). There were no significant differences in LV mass or LV ejection fraction between the three groups. Either normal saline (n = 60) or isoproterenol (n = 55) was then administered intraperitoneally (50 mg/kg/day) for 5 days/wk for two consecutive weeks to induce LVH. Body weight decreased significantly in the PrP(-/-) group (18%). On multivariate analysis, higher LV mass index posttreatment was independently associated with the tga20 group (versus PrP(-/-) versus WT, p = 0.002) after adjusting for treatment (isoproterenol versus saline), and weight change (r(2) = 0.13 for model, p = 0.016). Therefore, PrP(C) appears unrelated to LV mass and function in the basal state. Isoproterenol causes transient enhancement of PrP(C) expression in WT mice and a more pronounced increase in tga20 mice at 2 h posttreatment. Overexpression of PrP(C) in the tga20 group may be associated with higher LV mass after a 2 wk regimen of isoproterenol.