Severe complications from<unk><unk>  Scleroderma (Scleroderma) can include:
Untreated high blood pressure that strains the heart
enlargement of the heart, which leads to heart failure
pericardial effusion
arrhythmias (both atrial and ventricular)
conduction system defects
valvular abnormalities
myocardial ischaemia
myocardial hypertrophy
It's generally thought cardiac disease is a major cause of death from scleroderma, or that it often contributes to death, though cardiac disease is only reported in about 10 percent of cases.  Conduction abnormalities, myocardial and pericardial disease disease may also be common.  Some have suggested a 'cardiac Raynaud's phenomenon' exists, but exactly how myocardial involvement develops in scleroderma is unclear.
An angiography-based study of 172 patients has suggested patients who may have obstructive epicardial disease associated with scleroderma should be treated the same as patients without scleroderma.
The heart in progressive systemic sclerosis 
The heart in rheumatoid arthritis
The heart in Wegener's granulomatosis
The heart in juvenile rheumatoid arthritis
The heart in sarcoidosis
The heart in mixed connective tissue disorder
The heart in temporal arteritis / giant cell arteritis
The heart in Behçet's disease