Clinical practice. The impact of lung disease on the heart and cardiac disease on the lungs.

Pathologies in both the respiratory and cardiovascular systems frequently coexist and impact on each other. This manuscript introduces an approach to the interpretation of this complex relationship. Pulmonary hypertension can be a significant consequence of many respiratory diseases. This in turn can lead to right ventricular dysfunction and cor pulmonale. Many childhood illnesses can result in cor pulmonale and can be conveniently grouped into three categories: idiopathic pulmonary hypertension, neonatal lung diseases, and lung disease beyond the neonatal period. When considering the impact of cardiac disease on the lung, one must consider two main pathologies: compression of the pediatric airway and increased lung water. In conclusion, thorough attention must be given to the interpretation of the complex relationship between cardiac and respiratory diseases. Pulmonary hypertension is a complication to consider in respiratory illness at all ages. In addition, when dealing with the complexities of congenital heart disease, one must always be aware of the risks of pulmonary complications whether parenchymal or airway. Ongoing improvements in ventilation strategies, vasodilator therapy, and surgical interventions continue to improve the outlook for these complex cases.