Noninvasive electroanatomic mapping of human ventricular arrhythmias with electrocardiographic imaging

The rapid heartbeat of ventricular tachycardia (VT) can lead to sudden cardiac death and is a major health issue worldwide. Efforts to identify patients at risk, determine mechanisms of VT, and effectively prevent and treat VT through a mechanism-based approach would all be facilitated by continuous, noninvasive imaging of the arrhythmia over the entire heart. Here, we present noninvasive real-time images of human ventricular arrhythmias using electrocardiographic imaging (ECGI). Our results reveal diverse activation patterns, mechanisms, and sites of initiation of human VT. The spatial resolution of ECGI is superior to that of the routinely used 12-lead electrocardiogram, which provides only global information, and ECGI has distinct advantages over the currently used method of mapping with invasive catheter-applied electrodes. The spatial resolution of this method and its ability to image electrical activation sequences over the entire ventricular surfaces in a single heartbeat allowed us to determine VT initiation sites and continuation pathways, as well as VT relationships to ventricular substrates, including anatomical scars and abnormal electrophysiological substrate. Thus, ECGI can map the VT activation sequence and identify the location and depth of VT origin in individual patients, allowing personalized treatment of patients with ventricular arrhythmias.

Marital discord and coronary artery disease: a comparison of behaviorally defined discrete groups

OBJECTIVE

Marital difficulties can confer risk of coronary heart disease, as in a study of outwardly healthy couples (T. W. Smith et al., 2011) where behavioral ratings of low affiliation and high control during marital disagreements were associated with asymptomatic coronary artery disease (CAD). However, taxometric studies suggest that marital discord is more accurately represented by discrete groups, rather than continuous dimensions. To determine if a categorical representation of marital discord was also related to CAD, discordant and nondiscordant groups were identified via cluster analysis in further analyses of the T. W. Smith et al. (2011) study.

METHOD

One hundred fifty healthy couples (M age = 63.5) completed a marital disagreement discussion, self-reports of anxiety and anger during the disagreement, and self-report measures of marital adjustment. CAD was measured as coronary artery calcification (CAC) via computed tomography scans.

RESULTS

In a 2-group cluster solution, 31% of couples were characterized as discordant, with higher levels of hostility and dominance and lower levels of warmth compared with the nondiscordant group. Discordant couples reported lower marital adjustment and greater negative affect during the discussion. Controlling biomedical and behavioral risk factors, discordant couples had greater CAC (p = .029, η² = .035). Discordant and nondiscordant groups defined via self-reported marital adjustment did not differ in CAC (p = .17, η² = .014).

CONCLUSIONS

Marital discord defined categorically and with behavioral observations was associated with greater levels of asymptomatic CAD. Marital discord is associated with higher risk at early stages of coronary heart disease, but commonly used self-reports may underestimate this risk.

Incremental validity of spouse ratings versus self-reports of personality as predictors of marital quality and behavior during marital conflict

The personality traits of neuroticism and agreeableness are consistently related to marital quality, influencing the individual's own (i.e., actor effect) and the spouse's marital quality (i.e., partner effect). However, this research has almost exclusively relied on self-reports of personality, despite the fact that spouse ratings have been found to have incremental validity over self-reports for a variety of other important outcomes. In a study of 300 middle-aged and older married couples, we examined the incremental validity of spouse ratings of neuroticism and agreeableness in predicting concurrent levels of self-reported marital quality, observations of behavior during a marital disagreement task, and depressive symptoms. Neuroticism and agreeableness had expected actor and partner effects on each of these outcomes. Spouse ratings of these traits demonstrated incremental validity in estimates of actor and partner effects on marital quality, marital behavior, and depressive symptoms. Results suggest that spouse ratings of personality may be important additions to the typical reliance on self-reports for research and clinical assessment in marriage.

Residual Cx45 and its relationship to Cx43 in murine ventricular myocardium

Gap junction channels in ventricular myocardium are required for electrical and metabolic coupling between cardiac myocytes and for normal cardiac pump function. Although much is known about expression patterns and remodeling of cardiac connexin(Cx)43, little is known about the less abundant Cx45, which is required for embryonic development and viability, is downregulated in adult hearts, and is pathophysiologically upregulated in human end-stage heart failure. We applied quantitative immunoblotting and immunoprecipitation to native myocardial extracts, immunogold electron microscopy to cardiac tissue and membrane sections, electrophysiological recordings to whole hearts, and high-resolution tandem mass spectrometry to Cx45 fusion protein, and developed two new tools, anti-Cx45 antisera and Cre(+);Cx45 floxed mice, to facilitate characterization of Cx45 in adult mammalian hearts. We found that Cx45 represents 0.3% of total Cx protein (predominantly 200 fmol Cx43 protein/μg ventricular protein) and colocalizes with Cx43 in native ventricular gap junctions, particularly in the apex and septum. Cre(+);Cx45 floxed mice express 85% less Cx45, but do not exhibit overt electrophysiologic abnormalities. Although the basal phosphorylation status of native Cx45 remains unknown, CaMKII phosphorylates 8 Ser/Thr residues in Cx45 in vitro. Thus, although downregulation of Cx45 does not produce notable deficits in electrical conduction in adult, disease-free hearts, Cx45 is a target of the multifunctional kinase CaMKII, and the phosphorylation status of Cx45 and the role of Cx43/Cx45 heteromeric gap junction channels in both normal and diseased hearts merits further investigation.

Perceptions of the cognitive compensation and interpersonal enjoyment functions of collaboration among middle-aged and older married couples

Perceptions of cognitive compensation and interpersonal enjoyment of collaboration were examined in three hundred middle-aged and older couples who completed measures of perceptions of collaboration, cognitive ability, marital satisfaction, an errand task and judged their spouse's affiliation. Older adults (especially men) endorsed cognitive compensation and interpersonal enjoyment and reported using collaboration more frequently than middle-aged adults. Greater need for cognitive compensation was related to lower cognitive ability only for older wives. Greater marital satisfaction was associated with greater interpersonal enjoyment. These two functions related to reports of more frequent use of collaboration and perceptions of spousal affiliation in a collaborative task.

Matters of the variable heart: respiratory sinus arrhythmia response to marital interaction and associations with marital quality

Maintenance of relationship quality requires self-regulation of emotion and social behavior, and women often display greater effort in this regard than do men. Furthermore, such efforts can deplete the limited capacity for self-regulation. In recent models of self-regulation, resting level of respiratory sinus arrhythmia, quantified as high-frequency heart rate variability (HF-HRV), is an indicator of self-regulatory capacity, whereas transient increases in HF-HRV reflect self-regulatory effort. To test these hypotheses in marriage, 114 young couples completed measures of marital quality and a positive, neutral, or negative initial marital task, preceded and followed by resting baseline assessments of HF-HRV. Couples then discussed a current marital disagreement. Resting HF-HRV was correlated with marital quality, suggesting that capacity for self-regulation is associated with adaptive functioning in close relationships. For women but not men, the negative initial task produced a decrease in resting HF-HRV. This effect was mediated by the husbands' negative affect response to the task and their ratings of wives as controlling and directive. When the subsequent disagreement discussion followed the negative initial task, women displayed increased HF-HRV during the discussion but a decrease when it followed the neutral or positive task. The valence of the initial task had no effect on men's HF-HRV during disagreement. Negative marital interactions can reduce women's resting HF-HRV, with potentially adverse health consequences. Women's reduced health benefit from marriage might reflect the depleting effects on self-regulatory capacity of their greater efforts to manage relationship quality.

Interpersonal circumplex descriptions of psychosocial risk factors for physical illness: application to hostility, neuroticism, and marital adjustment

Personality risk factors for physical illness are typically studied individually and apart from risk factors reflecting the social environment, potentially fostering a piecemeal understanding of psychosocial influences on health. Because it can be used to describe both personality and social relationship processes, the interpersonal circumplex (IPC) provides an integrative approach to psychosocial risk. In 301 married couples we examined IPC correlates of 3 risk factor domains: anger, hostility, and aggressiveness; neuroticism; and marital adjustment. Risk factors displayed IPC locations ranging from hostile dominance (e.g., verbal aggressiveness, marital conflict) to hostility (e.g., anger) to hostile submissiveness (e.g., anxiety, depression); protective factors (marital satisfaction and support) reflected warmth or friendliness in the IPC. Similar descriptions were found using self-reports and spouse ratings of IPC dimensions, indicating that interpersonal styles associated with risk factors do not simply reflect common method variance. Findings identify interpersonal processes reflecting low affiliation or high hostility as a common component of risk and indicate distinctions among risk factors along the dominance dimension.

Provider and recipient factors that may moderate the effectiveness of received support: examining the effects of relationship quality and expectations for support on behavioral and cardiovascular reactions

Social relationships have been shown to predict decreased risk for morbidity and mortality. However, the more precise processes underlying these associations are in need of exploration. In this study, we examined important provider (relationship quality) and recipient-related (support expectations) factors that might influence the effectiveness of receiving support on cardiovascular reactivity (CVR). Participants discussed a stressful event with either a supportive or ambivalent friend, and were either given instructions that included an explicit expectation of support provision or no expectation during the task. Behavioral coding revealed fewer emotionally supportive behaviors and marginally more negative behaviors from ambivalent friends. Receiving support from an ambivalent friend was also associated with higher systolic blood pressure reactivity compared to a supportive friend, but had no effects on diastolic blood pressure or heart rate; nor were there any significant statistical interactions with the expectation manipulation. Overall, support expectations had little influence on cardiovascular and behavioral responses. Implications for the study of received support and health are discussed along with potential mechanisms responsible for such links.

Components of Negative Affectivity and Marital Satisfaction: The Importance of Actor and Partner Anger

Marital satisfaction is inversely associated with neuroticism in oneself (actor effects) and one's spouse (partner effects). However, different facets of neuroticism, particularly angry hostility in comparison to depression or anxiety, may have differential effects on relationship quality. The present study examined actor and partner effects of anxiety, angry hostility, and depression facets of neuroticism on marital satisfaction in 301 couples. All path analyses demonstrated that depression and angry hostility had equivalent, significantly negative actor effects on marital satisfaction, but only angry hostility had a significant negative partner effect. Hence, in examining marital adjustment, the distinction between the various facets of neuroticism may be important. Further, anger may be an important but understudied consideration in research on marital discord.

Social ties and cardiovascular function: an examination of relationship positivity and negativity during stress

The quality and quantity of one's relationships have been reliably linked to morbidity and mortality. More recently, studies have focused on links between relationships and cardiovascular reactivity as a physiological mechanism via the stress-buffering hypothesis. However, not all social relationships are consistently positive which points to the importance of a more comprehensive examination of relationship that includes negative qualities. In this study, we manipulated relationship positivity and negativity with an experimenter and examined its influence on cardiovascular reactivity. Results revealed that relationship positivity was associated with lower systolic blood pressure (SBP) reactivity for men and women. Relationship negativity, on the other hand, was related to less of an increase in diastolic blood pressure (DBP) reactivity in men. Internal analyses showed that perceptions of positivity and negativity interacted such that high positivity/high negativity perceptions (ambivalence) were related to the highest SBP reactivity. Results of this study suggest that the quality of one's relationships is an important moderator of cardiovascular reactivity during stress.

Conflict and collaboration in middle-aged and older couples: I. Age differences in agency and communion during marital interaction

Prior theory and research regarding age differences in marital interaction suggest that older couples display and experience more positivity and less negativity than middle-aged couples. However, studies of overt behavior in older couples are relatively rare and have emphasized disagreement, neglecting other important contexts for older couples such as collaboration during everyday problem solving. Further, the affiliation or communion dimension of social interaction (i.e., warmth vs. hostility) is commonly assessed but not the control or agency dimension (e.g., dominance vs. submissiveness). The present study examined affect, cognitive appraisals, and overt behavior during disagreement (i.e., discussing a current conflict) and collaboration (i.e., planning errands) in 300 middle-aged and older married couples. Older couples reported less negative affect during disagreement and rated spouses as warmer than did middle-aged couples. However, these effects were eliminated when older couples' greater marital satisfaction was controlled. For observed behavior, older couples displayed little evidence of greater positivity and reduced negativity-especially women. During collaboration, older couples displayed a unique blend of warmth and control, suggesting a greater focus on emotional and social concerns during problem solving.

Conflict and collaboration in middle-aged and older couples: II. Cardiovascular reactivity during marital interaction

Marital strain confers risk of cardiovascular disease (CVD), perhaps though cardiovascular reactivity (CVR) to stressful marital interactions. CVR to marital stressors may differ between middle-age and older adults, and types of marital interactions that evoke CVR may also differ across these age groups, as relationship contexts and stressors differ with age. The authors examined cardiovascular responses to a marital conflict discussion and collaborative problem solving in 300 middle-aged and older married couples. Marital conflict evoked greater increases in blood pressure, cardiac output, and cardiac sympathetic activation than did collaboration. Older couples displayed smaller heart rate responses to conflict than did middle-aged couples but larger blood pressure responses to collaboration-especially in older men. These effects were maintained during a posttask recovery period. Women did not display greater CVR than men on any measure or in either interaction context, though they did display greater parasympathetic withdrawal. CVR to marital conflict could contribute to the association of marital strain with CVD for middle-aged and older men and women, but other age-related marital contexts (e.g., collaboration among older couples) may also contribute to this mechanism.

Interpersonal Circumplex Octant, Control, and Affiliation Scales for the NEO-PI-R

The Five Factor Model (FFM) traits of agreeableness and extraversion are rotational equivalents of the interpersonal circumplex (IPC) dimensions of affiliation and control. Given that the NEO-PI-R is a widely used measure of the FFM, availability of IPC dimension scales within this inventory could facilitate integration of FFM and interpersonal perspectives. In a study of 301 married couples, we evaluated an IPC scoring system for the NEO-PI-R (Wiggins & Trobst, 1998) comprising 6-item octant scales and composites representing control and affiliation. The octant scales demonstrated expected circular structure. Octant and dimension scales demonstrated convergent and discriminant validity, in analyses of self-report and spouse-rating versions of this IPC measure and the Impact Message Inventory. Further, extraversion corresponded to friendly dominance in the IPC and agreeableness to submissive friendliness.

Relationship quality and CPAP adherence in patients with obstructive sleep apnea

The prospective influence of relationship support and conflict on adherence to continuous positive airway pressure (CPAP) was examined over the first 3 months of CPAP treatment in 42 married, male patients with obstructive sleep apnea (OSA). CPAP adherence reports were available for 23 patients. Patient ratings of marital conflict predicted average nightly adherence (beta = -0.357, p < .05), but ratings of marital support did not predict adherence. Three-month follow-up ratings of marital support and conflict, subjective sleepiness, depression, and functional impairment were available for 16 patients from the first sample. Six additional patients without adherence reports provided baseline and 3-month follow-up questionnaire data, which resulted in a total of 22 patients with follow-up questionnaire data. Following 3 months of CPAP, patients reported decreased marital conflict (d = 0.43, p < .05), sleepiness (d = 1.13, p < .001), depression (d = 0.73, p < .001), and functional impairment (d = 1.48, p < .001). These findings highlight the importance of evaluating marital conflict for OSA patients and suggest marital conflict may be a target for interventions to improve CPAP adherence.

Associations of self-reports versus spouse ratings of negative affectivity, dominance, and affiliation with coronary artery disease: where should we look and who should we ask when studying personality and health?

OBJECTIVE

Aspects of negative affect and social behavior studied as risk factors for coronary heart disease are usually examined separately and through self-reports. Using structural models of these personality domains, we tested associations of self-reports and spouse ratings of anxiety, depressive symptoms, anger, affiliation and dominance with coronary artery disease (CAD).

DESIGN

In 154 healthy older couples, the authors tested cross-sectional associations with CAD of three facets of negative affectivity and two dimensions of the Interpersonal Circumplex, (IPC) using scales derived from the NEO-PI-R.

MAIN OUTCOME MEASURES

CAD was quantified as Agatston scores from CT scans of coronary artery calcification (CAC).

RESULTS

Self-reports were generally unrelated to CAC, whereas spouse ratings were consistently associated, largely independent of potential confounds. When considered simultaneously, anxiety and anger were related to CAC but depression was not. When considered together, both dominance and (low) affiliation were related to CAC.

CONCLUSIONS

Structural models of negative affectivity and social behavior can facilitate integrative study of psychosocial risk factors. Further, self-report measures of these traits might under-estimate related CHD risk.

The management of deformities of the foot in children with spina bifida

A simple photographic technique is described which measures the weight-bearing and non-weight-bearing areas of the feet in the standing child. The child stands on a rectangular sheet of thick glass which is set into the floor. Beneath the floor is a cellar, from which the soles of the feet may be observed and photographed. A transparent grid placed over the photographic print enables the weight-bearing and non-weight-bearing areas of the foot to be measured, and thus to express the weight-bearing areas as a percentage of the total area of the sole of the foot. The procedure was used to assess 55 spina-bifida children who had had surgical correction of deformities of the feet. The findings are discussed.

Interpersonal responses among sibling dyads tested for BRCA1/BRCA2 gene mutations

OBJECTIVE

The familial context plays an important role in psychosocial responses to genetic testing. The purpose of this study was to compare sibling pairs with different combinations of BRCA1/BRCA2 test results on measures of affect, interpersonal responses, and physiological reactions.

DESIGN

Forty-nine sibling dyads with different combinations of BRCA1/BRCA2 test results (i.e., mixed, positive, negative) completed a questionnaire, and 35 of the dyads also participated in a laboratory-based discussion of genetic testing.

MAIN OUTCOME MEASURES

The primary outcome variables included participant reports of supportive actions toward their sibling, state anger and anxiety, perceptions of sibling behavior, and electrodermal responses.

RESULTS

Compared to positive and negative dyads, mixed pairs reported less friendly general support actions, noted more anger, and perceived their sibling to be less friendly and more dominant during the interactions. In comparisons between same-result (i.e., positive, negative) pairs, positive dyads reported more dominant support behaviors and perceived their sibling to be friendlier during the interactions.

CONCLUSION

Data suggest that siblings who have different test results may experience more interpersonal strain than siblings who have the same test result. Future research on genetic testing and family relationships can expand upon these findings.