Coconut Atrium Causing Restrictive Physiology in the Right Ventricle

We herein report a 61-year-old woman with a history of mitral valve replacement for rheumatic fever who presented with crural edema and ascites. Computed tomography showed massive left atrial (LA) calcification involving the interatrial septum, termed "coconut atrium." Catheterization revealed not only pulmonary artery hypertension but also a large V-wave in the pulmonary artery wedge pressure waveform and a dip-and-plateau pattern of right ventricular pressure. Three-dimensional transthoracic echocardiography confirmed the early attainment of peak LA volume and a decreased LA expansion index. Stiff LA syndrome due to coconut LA results in the development of restrictive right ventricular physiology.

Correlation between left atrial expansion index and stroke subtype: A 10-Year Follow-Up Study

PURPOSE

Although left atrial (LA) expansion index predicts cardiovascular events, its efficacy for predicting cerebral events is unknown.

METHODS

This study enrolled 2205 patients who had sinus rhythm after echocardiography in their first visit. LA expansion index was calculated as (Vol_max -Vol_min ) x100%/Vol_min , where Vol_max was defined as maximal LA volume and Vol_min as minimal LA volume. The study endpoint was ischemic stroke. Stroke subtype was classified as cardioembolic stroke (CE), noncardioembolic stroke with determined mechanism (NCE), or embolic stroke of undetermined source (ESUS).

RESULTS

Over a 10-year (mean 9.7 years) follow-up period, 128 (5.8%) participants reached endpoint, including 46 with CE, 33 with NCE, and 49 with ESUS. Regardless of stroke subtype, LA expansion index was lower in the event groups compared to the nonevent group. The lowest quartile of LA expansion index was associated with high CHA₂ DS₂ -VASc score at enrollment and more events, including CE, ESUS, atrial fibrillation (AF), heart failure, and all-cause mortality, relative to other quartiles. The LA expansion index was an independent predictor of CE (HR 0.82; 95% CI 0.723-0.912, per 10% increase in LA expansion index; P < .0001) and ESUS (HR 0.92; 95% CI 0.881-0.976, per 10% increase in LA expansion index; p 0.003). An LA expansion index <68% predicts the presence of AF after ESUS with 84% sensitivity and 70% specificity.

CONCLUSION

LA expansion index is useful for predicting CE and ESUS. It is also associated with AF, heart failure hospitalization, and all-cause mortality.

Relationship of left atrial expansion index to exercise tolerance, pretest probability of restenosis, and positive predictive value of treadmill test in coronary artery disease

BACKGROUND

Whether left atrial (LA) expansion index is associated with coronary restenosis, and exercise capacity (EC) reduction in coronary artery disease has not been established.

METHODS

This study analyzed 342 consecutive patients who had received a coronary stent implant. A treadmill exercise test (TET) was administered in all participants. The LA expansion indices were measured immediately before and after TET. Maximal EC measured on a breath-by-breath basis by a metabolic cart with gas analyzers and recorded as metabolic equivalent task. All patients with positive TET results received angiography, and those with restenosis received complete revascularization by either percutaneous coronary intervention (PCI) or bypass surgery. The LA expansion index and EC before and 1 month after PCI were then compared.

RESULTS

Out of 342 patients, 74 had positive TET results, and 54 had restenosis in angiography. Low LA expansion index was associated with poor EC. In patients with LA expansion index > 200%, only 5% had restenosis with 38.5% positive predictive value (PPV) of TET. In patients with LA expansion index < 100%, however, 64.3% had restenosis with 94.7% PPV of TET. Restenosis induced low pre-TET LA expansion index and further decline during TET. The LA expansion index significantly (P .001) improved from 133 ± 64% before PCI to184 ± 86% after PCI, and the improvement corresponded with EC recovery. A 10% reduction in LA expansion index was associated with a 15% increase in pretest probability of restenosis.

CONCLUSION

The LA expansion index is associated with EC, pretest probability of restenosis, and PPV of TET. Revascularization improves both EC and LA expansion index.

Left Atrial Expansion Index Predicts Left Ventricular Filling Pressure and Adverse Events in Acute Heart Failure With Severe Left Ventricular Dysfunction

BACKGROUND

The power of left atrial (LA) parameters for predicting left ventricular (LV) filling pressure and adverse events in acute heart failure (HF) with severe LV dysfunction, either sinus rhythm or atrial fibrillation (AF), is not fully understood.

METHODS AND RESULTS

Echocardiography was performed in 141 patients with acute decompensated congestive HF and LV ejection fraction <35%, including 42 with permanent AF. The LA expansion index was calculated as (Volmax - Volmin) × 100%/Volmin, where Volmax was defined as maximal and Volmin as minimal LA volume. Of 141 patients, invasive LV filling pressures within 12 hours of LA expansion index measurement were available in 109. The end points were 3-year frequencies of HF hospitalization and all-cause mortality. Over a median follow-up of 3.1 years, 74 participants (52.5%) reached the end points (sinus vs AF group: 48.5% vs 61.9%, respectively; P = .047). Multivariate analysis revealed that adverse events of both groups were only independently associated with age and LA expansion index. Rates of adverse events were proportional to LA expansion index. There was a good logarithmic relationship between LA expansion index and LV filling pressure, regardless of presence or absence of AF.

CONCLUSIONS

LV filling pressure can be estimated well by LA expansion index, with or without AF. The LA expansion index predicts adverse events in HF patients with severe systolic dysfunction. (ClinicalTrials.gov number: NCT01307722).